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J L Lyon

Publications and source records attributed to J L Lyon.

At least 19 recordsLinked to original sources
PubMed1996

Is diabetes mellitus a risk factor for ovarian cancer? A case-control study in Utah and Washington (United States).

Insulin resistance characterizes non-insulin dependent diabetes (NIDDM). Insulin resistance may coexist in clinical syndromes with hyperestrogenism and hyperandrogenism, suggesting that the ovary may be sensitive to effects of insulin. In addition, insulin-like growth factor-I receptors, which are capable of binding insulin, have been identified in ovarian cancer tissue and are proposed to regulate cell growth. We evaluated the association between a history of diabetes mellitus and ovarian cancer in a case-control study in seven counties in Washington and in Utah (United States) during the years 1975-87. Cases included women newly diagnosed with ovarian cancer over a five-year period who were identified through population-based cancer reporting. Controls similar to cases with regard to age and county of residence were identified via household surveys or random digit dialing. The study included 595 cases and 1,587 controls. Twenty-seven cases (4.5 percent) and 72 controls (4.5 percent) reported a history of diabetes. Logistic regression analysis of the association between diabetes and ovarian cancer controlling for age, body mass index, and race resulted in an odds ratio (OR) of 0.9 (95 percent confidence interval [CI] = 0.6-1.5). The OR was not changed with further controlling for prior oral contraceptive use or prior pregnancy. None of the 20 women with nonepithelial tumors (15 of which were stromal tumors) had a history of diabetes (upper CI = 4.0). These results, together with findings of two earlier cohort studies, do not support the hypothesis that diabetes is a risk factor for epithelial ovarian cancer.

Adult↗
PubMed1996

Nasopharyngeal cancer in a low-risk population: defining risk factors by histological type.

Nasopharyngeal cancer (NPC) is a major public health problem in parts of Southeast Asia and North Africa, but is rare among whites and blacks. Although infection with the EBV and genetic susceptibility appear to play large roles in high-incidence populations, migrant studies suggest that environmental factors may also be important. Aside from the high risks associated with ingestion of salted fish, surprisingly few other risk factors have been established from studies in endemic areas. We studied a low-incidence population to determine whether tobacco use, alcohol consumption, and certain medical conditions and treatments are related to NPC and to examine variations in risk by histology. We reasoned that new relationships might be best identified in the absence of strong causal pathways, such as intake of preserved foods and genetic susceptibility. A population-based case-control study was conducted from 1987 to 1993 at five cancer registries in the United States: western Washington, metropolitan Detroit, Connecticut, Iowa, and Utah. Controls were identified by random digit dialing and frequency matched to the gender and age distribution of cases at each registry. Telephone interviews were completed by 231 cases and 246 controls. We observed a strong dose-response relationship between cigarette smoking and risk of differentiated squamous cell carcinoma (test for trend, P < .001). The highest risk [odds ratio (OR), 6.5; 95% confidence interval (CI), 2.0-21.3] occurred among current smokers with a history of more than 60 pack-years. In contrast, there was no evidence that undifferentiated or nonkeratinizing carcinomas were associated with cigarette smoking. Similarly, a significant increase in risk was observed for the heaviest alcohol consumers (21 or more drinks/week) only for differentiated squamous cell carcinomas (OR, 2.9; 95% CI, 1.2-6.9). The associations with cigarettes and alcohol appeared to be stronger among persons 50 years or older. There was a suggestion that diagnosis with infectious mononucleosis (a marker of late infection with EBV) is linked with decreased NPC risk (OR, 0.4; 95% CI, 0.1-1.1). This report indicates that over two-thirds of differentiated squamous cell NPC cases arising in older persons in the United States can be accounted for by cigarettes and alcohol, but leaves unexplained cases arising in the young and carcinomas of undifferentiated or nonkeratinizing histology. Future studies of NPC need to take into account histology and age in evaluating these and other environmental and genetic risk factors.

Adult↗
PubMed1995

The incidence of iliac, femoral, and popliteal artery aneurysms in hospitalized patients.

PURPOSE: Previous studies have attempted to determine the incidence and mortality rate of abdominal aortic aneurysms in a variety of populations; however, the incidence of iliac, femoral, and popliteal artery aneurysms have not been established. The objective of this study was to determine the incidence of lower extremity aneurysms in hospitalized patients in the state of Utah, which has a population at low risk for cardiovascular disease, atherosclerosis, and smoking, and to compare the results with the incidence in the United States. METHODS: Incidences of iliac, femoral, and popliteal artery aneurysm in Utah were determined over a 6-year period, with data obtained via diagnostic codes from the Utah Hospital Association. The incidence of iliac, femoral, and popliteal artery aneurysms in the United States hospital population was calculated by use of National Hospital Discharge Summary 1990 data, a complex sample of nonfederal short-stay hospitals in the United States, which provides the most comprehensive database of health statistics in the United States. RESULTS: The incidence of iliac femoral/popliteal artery aneurysms in hospitalized Utah men is 3.76 and 4.85 per 100,000 population, respectively. In American men, iliac and femoral/popliteal artery aneurysm incidences are 6.58 and 7.39 per 100,000 population, respectively. Incidences among hospitalized women in Utah are 0.24 and 1.07 per 100,000; incidences in women in the United States are 0.26 and 1.00 per 100,000, respectively. The incidence of nonaortic peripheral aneurysms among hospitalized patients in Utah is lower than in the United States. The rate ratios (Utah/United States) for incidences of iliac, femoral, and popliteal artery aneurysms in men are 0.57 and 0.66, respectively (p < 0.05). No statistical difference is seen between incidences in women in Utah and the United States (p > 0.05)-ratios of 0.93 and 1.06, respectively. CONCLUSION: This study validates the traditional belief that iliac, femoral, and popliteal artery aneurysms are much less frequent, at least in hospitalized patients, than previously published incidences of abdominal aortic aneurysms.

Adult↗
PubMed1995

Maternal exposure to N-nitrosatable drugs as a risk factor for childhood brain tumours.

BACKGROUND: Animal models suggest that compounds containing a nitrosyl group (N-nitroso compounds (NNO)) can act as potent transplacental carcinogens. Many common drug formulations have the potential to undergo nitrosation in vivo. The association between maternal use of nitrosatable drugs during pregnancy and development of brain tumours in the offspring was examined in a SEER-based case-control study. METHODS: Maternal exposure to nitrosatable drugs during pregnancy was compared among 361 childhood brain tumour cases and 1083 matched controls recruited through random-digit dialing. RESULTS: There was no increase in risk observed for childhood brain tumours overall (OR = 1.15; 95% CI: 0.69-1.94) or for astrocytomas individually (OR = 1.16; 95% CI: 0.50-2.69). A slight elevation in risk was noted for medulloblastomas (OR = 1.47; 95% CI: 0.28-7.62) and 'other' tumours (OR = 1.27; 95% CI: 0.56-2.86), however, both estimates were based on small numbers. CONCLUSIONS: Our findings suggest that no increased risk of childhood brain tumours was associated with maternal exposure to nitrosatable drugs. The study results should be viewed with caution given the imprecision of the point estimates as well as the lack of data on specific timing and dosage of exposure and degree of nitrosatability of drugs taken.

Astrocytoma↗
PubMed1995

The Utah Leukemia Case-Control Study: dosimetry methodology and results.

This paper discusses the dosimetry methodology used to estimate bone marrow dose and the results of dosimetry calculations for 6,507 subjects in an epidemiologic case-control study of leukemia among Utah residents. The estimated doses were used to determine if a higher incidence of leukemia among residents of Utah could have been attributed to exposure to radioactive fallout from above-ground nuclear weapons tests conducted at the Nevada Test Site. The objective of the dosimetry methodology was to estimate absorbed dose to active marrow specific to each case and each control subject. Data on the residence of each subject were available from records of the Church of Jesus Christ of Latter-day Saints. Deposition of fallout was determined from databases developed using historical measurements and exposure for each subject from each test was estimated using those data. Exposure was converted to dose by applying an age-dependent dose conversion factor and a factor for shielding. The median dose for all case and control subjects was 3.2 mGy. The maximum estimated mean dose for any case or control was 29 +/- 5.6 mGy (a resident of Washington County, UT). Uncertainties were estimated for each estimated dose. The results of the dosimetry calculations were applied in an epidemiological analysis.

Adolescent↗
PubMed1995

The Utah Thyroid Cohort Study: analysis of the dosimetry results.

Above ground testing of nuclear weapons at the Nevada Test Site (NTS) during the 1950s created radioactive fallout that was dispersed into the atmosphere and deposited over a large geographical area of the U.S. One area believed to have received a considerable amount of exposure to radioiodines (131I and 133I) in the fallout was southwest Utah and southeast Nevada. This paper describes the estimates of doses to the thyroid for a cohort of 3,545 subjects who were children during the atmospheric testing period. This group of children was examined for thyroid disease during 1965-1970 and again in 1985-1986. The cohort was made up of children who lived in three counties in 1965: Washington County, Utah; Lincoln County, Nevada; and Graham County, Arizona (originally thought to be an unexposed group). Pathway analysis was used in the dosimetry, considering exposures through the ingestion of milk and vegetables, inhalation of iodine during the passage of the fallout cloud, and external exposure. Specific data were obtained on diet (including sources and levels of milk and vegetables consumed, residence history, and lifestyle) by interviewing the parents or nearest living relative of subjects. The final dosimetry file for each member of the cohort contained specific doses to the thyroid glands and uncertainties (reported as geometric standard deviations, GSD) related to each dose estimate. The mean absorbed dose to the thyroid for subjects living in Washington County, Utah, was 170 mGy; for Lincoln County, Nevada, 50 mGy; and for those living in Graham County, Arizona, 13 mGy. The maximum dose to any subject was 4,610 mGy. There were 10 subjects who had doses greater than 1 Gy. The majority of uncertainty values calculated in this study were GSD values between 2.0 and 4.0. The results of the dosimetry were combined with the results of clinical examinations of the cohort to determine if a causal relationship exists between dose to thyroid from NTS generated radioactive iodines and the incidence of thyroid disease.

Adult↗
PubMed1995

Surgical trends in the treatment of diseases of the lumbar spine in Utah's Medicare population, 1984 to 1990.

Chronic low back pain is a major source of disability in this country. The rate of surgical treatment for back disorders varies between small geographic areas in the northeastern United States. A statewide database was utilized to determine rate of surgery for mechanical low back problems in Utah's Medicare population from 1984 to 1990. The average surgery rate for Medicare enrollees was 274.7 per 100,000, and the Utah laminectomy and discectomy rates were at least 20% higher than the U.S. average. Back surgery rates rose by 55% over the study period, primarily because of increasing rates of surgery for spinal stenosis. There was statistically significant variation in surgery rates among regions in the state, with the highest region having a rate 50% greater than the lowest region. Rates of surgery for spinal stenosis had more variation than those for herniated disc surgery. There was no significant correlation between the number of surgeons performing back surgery and the rate of surgery. The variation and increase in back surgery rates in Utah's Medicare population are likely related to changes in the use of surgery for treatment of spinal stenosis and not to an increase in the number of back surgeons. Further investigation is needed to understand better the reasons for the observed increase in back surgery rates.

Diskectomy↗
PubMed1994

The role of family history in risk of childhood brain tumors.

BACKGROUND: Although brain tumors are the second most frequent malignancy in children, relatively little is known about the role of family history in risk of these tumors. METHODS: Children under the age of 18 years (n = 361) in whom primary brain tumors were diagnosed were identified from eight United States population-based Surveillance, Epidemiology, and End Results registries and compared to matched controls (n = 1083) identified by random-digit dialing. Information regarding family history of birth defects or tumors was obtained, along with data on other potential risk factors, from interviews with the mothers and fathers of the index children. RESULTS: No significant differences were found in family history of epilepsy. However, moderate elevations in risk were observed for a history of birth defects in maternal relatives, particularly for female propositi. Significantly more mothers (odds ratio [OR] = 1.63, 95% confidence limits [CL] = 1.03, 2.57) and maternal female relatives (OR = 2.15, 95% CL = 1.14, 4.06) of cases than of controls were reported to have had birth defects. History of birth defects in maternal relatives was particularly associated with childhood brain tumors of "other" (not astrocytoma or medulloblastoma) histologic type (OR = 2.37, 95% CL = 1.25, 4.53) and infratentorial tumors (OR = 1.76, 95% CL = 1.06, 2.93). Slight excesses of tumors were observed in paternal relatives of children with astrocytomas (OR = 1.43, 95% CL 0.93, 2.20) or with infratentorial tumors (OR = 1.46, 95% CL 0.97, 2.20). Risk of childhood brain tumors did not increase with the number of relatives affected with brain tumors, breast cancer, leukemia or lymphoma, soft tissue sarcomas, or all of these tumor types combined (the Li-Fraumeni syndrome). CONCLUSIONS: These findings suggest a modest increase in risk of childhood brain tumors associated with maternal family history of birth defects. Family history of tumors does not appear to contribute appreciably to an increased risk of brain tumors in children.

Adolescent↗
PubMed1994

Cancer incidence among Mormons and non-Mormons in Utah (United States) 1971-85.

We calculated age-adjusted incidence rates per 100,000 by religion (Mormon, non-Mormon) for Utah (United States) using the 49,182 cancer cases occurring between 1971-85. For all causes of cancer, the rate in Utah for male members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormons) was about 24 percent less than the comparable US rate. There was a 50-percent lower rate of cancers associated with cigarette smoking among LDS men. Non-LDS (NLDS) men in Utah experienced an incidence of smoking-associated cancers slightly higher than other US men. LDS men had an incidence of those cancers not associated with smoking slightly lower than US men, and NLDS men had a 40-percent higher rate than US men because of higher rates of melanoma and cancers of the lip and prostate gland. LDS women had an all-sites cancer rate 24 percent below the comparable US rate, and a 60-percent lower rate of smoking-associated cancers. The incidence of cancer not associated with smoking was 20 percent lower for LDS women compared with US women and was the result of lower rates of cancers of the colon, breast, and uterine cervix. NLDS women had a 13-percent higher incidence of cancers not associated with smoking because of higher rates of cancers of the lip and breast.

Age Factors↗
PubMed1994

Exposure to hair-coloring products and the risk of multiple myeloma.

An interview study of persons diagnosed with multiple myeloma between 1977 and 1981 and suitable control subjects was conducted to test the hypothesis that exposure to hair dyes increases the risk of multiple myeloma. Among women, there was little evidence that prior regular use of hair dyes (odds ratio [OR] = 1.0; 95% confidence interval [CI] = 0.70, 1.4) or prior employment as a hairdresser (OR = 1.1; 95% CI = 0.43, 2.7) increased risk; however, the former comparison was limited by the lack of detailed information concerning the exposure. Among men, there was a modest association of regular use of hair dyes (OR = 1.5; 95% CI = 0.75, 2.9) with myeloma, but this was based on a small number of exposed persons.

Beauty Culture↗
PubMed1994

Unexplained elevations of maternal serum alpha-fetoprotein in women with antiphospholipid antibodies: a harbinger of fetal death.

OBJECTIVE: To determine whether unexplained elevations of maternal serum alpha-fetoprotein (MSAFP) in women with antiphospholipid antibodies are associated with adverse pregnancy outcomes. METHODS: A retrospective cohort study was used to compare pregnancy outcomes between women with second-trimester MSAFP values equal to or greater than 2.5 multiples of the median (MoM) and less than 2.5 MoM. The cohort included 60 pregnancies in 47 women with medium to high positive levels of immunoglobulin (Ig) G anticardiolipin antibodies, lupus anticoagulant, or both. RESULTS: Thirteen pregnancies (22%) had elevated MSAFP values (median 3.6 MoM, range 2.5-12.6). Of these, amniotic fluid AFP was normal in seven and elevated in one. None of the elevated MSAFP levels were explained by fetal anomalies, current fetal death, multiple gestation, incorrect dates, or vaginal bleeding. Pregnancies with elevated MSAFP values had a significantly higher incidence of fetal death (eight of 13, 62%, versus three of 47, 6%) and perinatal loss (ten of 13, 77%, versus seven of 47, 15%) than those with normal MSAFP (P < .001, Fisher exact test). In these women, the sensitivity and specificity of an unexplained elevated MSAFP level in ascertaining fetal death were 73 and 90%, respectively. For perinatal loss, the sensitivity was 59% and the specificity was 93%. Of the placentas studied, infarction occurred in eight of nine (89%) among the women with elevated MSAFP. CONCLUSIONS: Unexplained second-trimester elevations of MSAFP are common in women with antiphospholipid antibodies and are significantly associated with fetal loss. Abnormalities in the fetoplacental barrier are implicated as part of the pathophysiology of antiphospholipid antibody-mediated pregnancy loss.

Antiphospholipid Syndrome↗
PubMed1994

Clinical consequences of antiphospholipid antibodies: an historic cohort study.

OBJECTIVE: To determine the risk of antiphospholipid antibody-related disorders in women with elevated levels of these antibodies. METHODS: We used an historic cohort study design. Surveys of medical and obstetric histories for the interval from initial antibody testing to the time of patient interview were used to calculate age-adjusted rates for the development of medical disorders associated with antiphospholipid antibodies. The cohort included 130 women with lupus anticoagulant, medium to high levels of immunoglobulin G anticardiolipin antibodies, or both. RESULTS: The median interval of study was 3.2 years (range 0.7-9.5, mean 3.7). Sixty-three subjects (48%) developed at least one new disorder during the study interval. The age-adjusted rates (per 1000 patient-years; +/- standard error) for the development of the disorders studied were as follows: thrombosis (156.8 +/- 30.0), cerebrovascular accident (93.8 +/- 25.1), amaurosis fugax (57.1 +/- 23.2), transient ischemic attack (170.4 +/- 27.6), systemic lupus erythematosus (9.8 +/- 3.8), and autoimmune thrombocytopenia (56.0 +/- 22.2). Of the 34 thrombotic events that occurred during the study interval, eight were associated with pregnancy and eight occurred while the patients were taking anticoagulant medications. CONCLUSIONS: Our subjects developed complications associated with antiphospholipid antibodies at a substantial rate, and almost half suffered at least one new event during the study interval. The high rate of thrombosis in individuals with antiphospholipid antibodies, especially associated with pregnancy, underscores the need to evaluate long-term anticoagulation in these patients.

Adult↗
PubMed1993

A cohort study of thyroid disease in relation to fallout from nuclear weapons testing.

OBJECTIVE: To estimate individual radiation doses and current thyroid disease status for a previously identified cohort of 4818 schoolchildren potentially exposed to fallout from detonations of nuclear devices at the Nevada Test Site between 1951 and 1958. DESIGN: Cohort analytic study. SETTING: Communities in southwestern Utah, southeastern Nevada, and southeastern Arizona. PARTICIPANTS: Individuals who were still residing in the three-state area (n = 3122) were reexamined in 1985 and 1986, and information on the subjects' and their mothers' milk and vegetable consumption during the fallout period was obtained by telephone interview (n = 3545). After exclusions to eliminate missing data and confounding factors, 2473 subjects were available for analysis. MAIN OUTCOME MEASURES: Individual radiation doses to the thyroid were estimated by combining consumption data with radionuclide deposition rates provided by the US Department of Energy and a survey of milk producers. Relative risk models adjusted for age, sex, and state were fitted using maximum likelihood to period prevalence data for thyroid carcinomas, neoplasms, and nodules. RESULTS: Doses ranged from 0 mGy to 4600 mGy, and averaged 170 mGy in Utah. There was a statistically significant excess of thyroid neoplasms (benign and malignant; n = 19), with an increase in excess relative risk of 0.7% per milligray. A relative risk for thyroid neoplasms of 3.4 was observed among 169 subjects exposed to doses greater than 400 mGy. Positive but nonsignificant dose-response slopes were found for carcinomas and nodules. CONCLUSIONS: Exposure to Nevada Test Site-generated radioiodines was associated with an excess of thyroid neoplasms. The conclusions are limited by the small number of exposed individuals and the low incidence of thyroid neoplasms.

Adolescent↗
PubMed1993

Parental smoking and risk of childhood brain tumors.

Data from a large, population-based, case-control study were analyzed to assess the role of parental smoking in childhood brain tumors. Parents of 361 cases, newly diagnosed between January 1, 1977 and December 31, 1981 and ascertained from eight Surveillance, Epidemiology, and End Results (SEER) program registries, and 1,083 controls had been interviewed. No significant differences in risks were found to be associated with maternal or paternal smoking at any time (odds ratio (OR) = 0.92 for mothers and 1.06 for fathers), during the year of birth of the child (which included both the prenatal and postnatal periods) (ORs = 0.84 for < 1 pack/day and 1.0 for > or = 1 pack/day for mothers, and 0.68 for < 1 pack/day and 1.07 for > or = 1 pack/day for fathers), or 2 years before the child was born, i.e., the pre-conception period (ORs = 0.75 for < 1 pack/day and 1.01 for > or = 1 pack/day for mothers, and 0.90 for < 1 pack/day and 1.15 for > or = 1 pack/day for fathers). Mothers were also specifically asked if they smoked during the pregnancy, and no association was found compared with never smokers (OR = 1.08, 95% confidence interval (CI) 0.80-1.45) or for ever-smokers who continued to smoke during pregnancy compared with those who stopped smoking during pregnancy (OR = 1.15, 95% CI 0.75-1.78). Finally, no significant increase in risk of brain tumors was found for the child's passive exposure to parental smoking during the period from birth to diagnosis of the brain tumor in the case. The lack of an effect of parental smoking was observed for both the major histologic types and locations of brain tumors. These findings and those from earlier studies provide no support for the hypothesis that parental cigarette smoking influences the risk of brain tumors in children.

Adult↗
PubMed1993

A case-control study of multiple myeloma and occupation.

Lifetime job histories from a population-based, case-control study were analyzed to investigate the relationship between multiple myeloma and employment in various occupations and industries. Interviews were obtained from 89% (692) of eligible incident cases and 83% (1683) of eligible controls. An elevated risk was observed among persons ever employed as painters [odds ratio (OR) = 2.1, 95% confidence interval (CI) = 1.2-3.6], particularly for those employed for 10 or more years (OR = 4.1, 95% CI = 1.8-10.4). A small excess risk was observed among agricultural workers employed for 10 or more years (OR = 1.3, 95% CI = 1.0-2.2), with a higher relative risk observed among farm laborers (OR = 1.8, 95% CI = 1.0-4.0). Among agricultural workers who reported having been highly exposed to pesticides, the OR was 5.2 (95% CI = 1.6-21.1). Some evidence, based on smaller numbers, was also found to support an association with firefighting and employment in the petroleum- and coal-products manufacturing industries. Little evidence was found to support the previously noted association with wood exposure, and no evidence for an association with employment in the rubber or petroleum refining industries was found. This study lends further support to previously reported associations between multiple myeloma and employment among painters and agricultural workers.

Adult↗
PubMed1993

Epidemiology of the M-component immunoglobulin types of multiple myeloma.

The purpose of this population-based case-control study was to learn whether risk factors differ for the individual immunoglobulin types of multiple myeloma. In particular, we sought to determine whether IgA and IgG myeloma were related to a history of exposure to reported IgA- and IgG-stimulating conditions, respectively, or to a history of selected occupational and physicochemical exposures. The M-component immunoglobulin type was determined from immunoelectrophoresis as reported in medical records, and exposure status was obtained through in-person interviews. IgG (56 percent) and IgA (22 percent) M-components predominated. For 17 percent of cases, no peak was found on immunoelectrophoresis; they were presumed to have light-chain myeloma. Persons with these three types of myeloma did not differ with respect to distributions of age or race, but a somewhat higher proportion of light-chain cases were women (58 percent cf 45 percent of all other cases). Detailed analysis of the IgA and IgG subtypes provided little evidence that they differ with respect to prior immune stimulation or employment in several specific jobs. IgA myeloma, but not IgG myeloma, was associated modestly with a history of exposure to chest and dental X-rays. Our study provides little evidence that IgA and IgG myeloma differ with respect to the risk factors examined.

Benzene↗
PubMed1993

The effect of age at smoking initiation on lung cancer risk.

It has been assumed that a younger age at initiation of cigarette smoking is associated with an increased risk of lung cancer, but previous studies have not adjusted for two strong risk factors, the amount smoked and duration smoked. We used data from a population-based case-control study with 282 histologically confirmed lung cancer cases matched to 3,282 random controls to determine whether age at initiation of smoking plays an independent role in the occurrence of lung cancer. After controlling for age, sex, and amount of tobacco exposure, men who began to smoke before age 20 had a substantially higher risk of developing lung cancer [odds ratio (OR) = 12.7; 95% confidence interval (CI) = 6.39-25.2] compared with men who began smoking at age 20 or older (OR = 6.03; 95% CI = 2.82-12.9). For women, the heavy increase in risk continued until age 25 (OR = 9.97; 95% CI = 4.68-21.2) compared with women who began smoking at age 26 or older (OR = 2.58; 95% CI = 0.53-12.4). There was no predisposition toward a specific histologic type of lung cancer. In this study, up to 52.4% of lung cancer cases in men and up to 73.0% of lung cancer cases in women could be attributed to this effect of early age of first smoking.

Adenocarcinoma↗