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Biomedical subjects

G D Friedman

Publications and source records attributed to G D Friedman.

At least 73 records · Page 4Linked to original sources
PubMed1993

Effect of fecal occult blood testing on mortality from colorectal cancer. A case-control study.

OBJECTIVE: To estimate by case-control methods the effect of screening using the fecal occult blood test (FOBT) on mortality from colorectal cancer and to examine the relation of that effect to the interval since the most recent screening test. DESIGN: A case-control study. SETTING: The Kaiser Permanente Medical Care Program of Northern California. PATIENTS: A total of 485 persons who developed fatal colorectal cancer after 50 years of age and 727 age- and sex-matched controls. MEASUREMENTS: History of screening FOBTs during the 5 years before case diagnosis. RESULTS: After adjustment for potentially confounding factors, an odds ratio of 0.69 (95% Cl, 0.52 to 0.91) was observed for exposure to at least one screening FOBT during the 5-year interval. The odds ratio was lowest for the first year after the most recent FOBT and rose to 1.00 three years after the last screening examination. False-negative results among cases in the 1 to 2 years before diagnosis contributed substantially to lowering the estimate of efficacy. CONCLUSIONS: These data suggest that a program of annual or biennial screening using FOBTs might lower population risk for mortality from colorectal cancer sufficiently to have important public health implications. However, the confidence intervals around our odds ratio estimates were wide. We therefore believe that additional data will be needed before making recommendations that FOBT screening be expanded.

Adenocarcinoma↗
PubMed1993

A prospective study of cigarette tar yield and lung cancer.

We examined the relationship of cigarette tar yield and other cigarette-usage characteristics in current smokers to the incidence of lung cancer in a study population of 79,946 Kaiser Permanente Medical Care Program members, aged 30-89 years, who completed a detailed, self-administered, smoking-habit questionnaire during the years 1979 through 1985. Mean length of follow-up was 5.6 years. There were 302 incident lung cancers, of which 89 percent occurred in current or former smokers. The tar yield of the current cigarette brand was unassociated with lung cancer incidence (relative risk [RR] = 1.02 per 1 mg tar-yield in men, 95 percent confidence interval [CI] = 0.98-1.05; RR = 0.99, CI = 0.96-1.03 in women). However, in long-term (> 20 years) smokers, the risk of lung cancer was decreased in women who had smoked filtered cigarettes for 20 or more years relative to lifelong smokers of unfiltered cigarettes (RR = 0.36, CI = 0.18-0.75), but not in men who had smoked filtered cigarettes for 20 or more years (RR = 1.04, CI = 0.58-1.87).

Adult↗
PubMed1993

Coffee, tea, and mortality.

Except for conflicting evidence about coffee and risk of coronary disease, coffee and tea are not linked to major causes of death. Because of widespread use of both beverages and limitations of prior studies, concern persists. Using Cox models (ten covariates) we studied relations in 128,934 persons to 4501 subsequent deaths. Except for slightly increased risk from acute myocardial infarction among heavier (> or = 4 cups/d) coffee users (relative risk versus nondrinkers = 1.4, 95% confidence interval = 1.0 to 1.9, P = 0.07), there was no increased risk of mortality for all deaths (relative risk per cup of coffee per day = 0.99, 95% confidence interval = 0.97 to 1.01; relative risk per cup of tea per day = 0.98, 95% confidence interval = 0.96 to 1.00) or major causes in adjusted analyses. Coffee was related to lower risk of liver cirrhosis death (relative risk per cup of coffee per day = 0.77, 95% confidence interval = 0.67 to 0.89). Use of both beverages was related to a lower risk of suicide, progressively lower at higher coffee intake (relative risk per cup of coffee per day = 0.87, 95% confidence interval = 0.77 to 0.98). We conclude that coffee and tea have no overall relation to mortality risk. If coffee increases coronary risk, this is balanced by an unexplained lower risk of other conditions, notably cirrhosis and suicide.

Adult↗
PubMed1993

Cigarette smoking, leukemia, and multiple myeloma.

To evaluate previously reported associations with cigarette smoking, the incidence of leukemia and multiple myeloma was determined with follow-up of up to 24 years of 57,224 never-smokers, 20,928 former smokers, and 64,839 current cigarette smokers who received multiphasic health checkups. Cigarette smoking was associated with the development of acute nonlymphocytic leukemia in men only (relative risk, 2.8; 95% confidence interval, 1.2 to 6.4). Chronic myeloid leukemia showed an association with smoking of borderline significance in men only. Chronic lymphocytic leukemia and multiple myeloma were not related to cigarette smoking. In the men with acute nonlymphocytic leukemia there was a suggestion of a dose-response relation but it was not statistically significant. The association of cigarette smoking with acute nonlymphocytic leukemia was not explained by alcohol or coffee consumption or exposure to occupational hazards. This study adds to the growing body of evidence that cigarette smoking predisposes to acute nonlymphocytic leukemia in men.

Adult↗
PubMed1993

Natural history of asymptomatic and symptomatic gallstones.

Review of the sparse literature on the prognosis of asymptomatic and mildly symptomatic gallstones reveals a diversity of methods, definitions, and groups of patients studied, which makes it difficult to draw conclusions. It appears that serious symptoms and complications develop in about 1% to 2% of patients with asymptomatic gallstones annually, with fewer complications developing in later years than in years soon after gallstones are discovered. In patients with stones with mild symptoms, rates of the development of complications are perhaps a little higher, about 1% to 3% per year. In patients who are initially mildly symptomatic, cholecystectomy for severe symptoms probably is undertaken in 6% to 8% per year in the early years, decreasing with longer follow-up. Other than symptoms, no factors related to prognosis have been established. Acute cholecystitis is the most common severe complication of gallstones. Based on follow-up studies, obstructive jaundice, cholangitis, pancreatitis, and cancer of the gallbladder are infrequent complications. Risk of subsequent colon cancer should not ordinarily be a factor when cholecystectomy is considered. Analyses of cost-effectiveness have not demonstrated substantial differences in life expectancy between patients with asymptomatic gallstones who undergo immediate open cholecystectomy compared with watchful waiting.

Cholecystectomy↗
PubMed1993

Risk factors for pancreatic cancer: an exploratory study.

An exploratory case-control study to detect risk factors for pancreatic cancer was conducted within a large cohort of people who had received multiphasic health checkups in the San Francisco Bay Area. Four hundred and fifty who later developed pancreatic cancer were compared with 2687 who did not with respect to 779 characteristics recorded at the checkups. There was strong confirmation that cigarette smoking and diabetes mellitus were associated with risk of subsequent pancreatic cancer. Higher levels of serum iron, iron saturation and body weight were also predictive. Less striking associations of interest were with the leukocyte count, pulse rate and certain questionnaire items suggesting non-specific health impairment. Past concerns about alcohol and coffee consumption were not confirmed.

Adolescent↗
PubMed1993

Alcohol consumption and insulin concentrations. Role of insulin in associations of alcohol intake with high-density lipoprotein cholesterol and triglycerides.

BACKGROUND: The relation between alcohol intake and insulin levels may explain, in part, the reported associations of alcohol with cardiovascular disease risk factors, including high-density lipoprotein (HDL) cholesterol, triglycerides, blood pressure, and glucose levels, each of which has been recognized as a component of the insulin resistance syndrome. METHODS AND RESULTS: Subjects included nondiabetic participants of the Kaiser Permanente Women Twins Study (1989 through 1990). Usual alcohol intake was assessed as part of a food frequency questionnaire. For women from twin pairs in which both twins drank (n = 338), an increment of 12 g of alcohol per day (about one drink) was associated with an 8% lower 2-hour post-glucose-load insulin (P < .01) in a multiple regression analysis for twin data, adjusted for age, body mass index, waist-to-hip ratio, total caloric intake, and family history of diabetes. With genetic influences removed by matched analysis of the subset of 98 monozygotic twin pairs, an intrapair difference of 12 g of alcohol per day was associated with a 12.4% intrapair decrement in postload insulin (P < .01). Inverse associations were also seen for fasting insulin. Alcohol consumption was inversely associated with postload glucose but not with fasting glucose in unmatched (P = .05) and matched (P = .005) analyses. A significant positive association of alcohol intake with high-density lipoprotein cholesterol and an inverse relation of alcohol intake with triglycerides were each independent of insulin levels (P < or = .02 in the matched models). Neither systolic nor diastolic blood pressures were related to alcohol consumption in this sample, perhaps because of the rather low level of alcohol intake in the study population (median, 4 g/d). CONCLUSIONS: Within the range of light to moderate drinking habits, alcohol consumption was inversely related to fasting and postload insulin levels. This relation did not explain associations of alcohol intake with lipid levels and may instead reflect an additional mechanism by which moderate alcohol consumption impacts cardiovascular disease risk.

Adult↗
PubMed1993

Exposure to engine exhaust and risk of subsequent cancer.

We evaluated the relation between occupational exposure to engine exhaust fumes and cancer risk among members of a large prepaid health plan who reported on exposure during a routine health examination (n = 160,230). Exposure in the past year was associated with an elevated risk of cancer of the thyroid (relative risk (RR) = 1.99; 95% confidence interval (CI), 1.01-3.92), female breast (RR = 1.53; CI, 1.00-2.33), nonbrain nervous system (RR = 2.26; CI, 1.09-4.67), and lip/tongue (RR = 1.82; CI, 1.09-3.04), and a decreased risk of melanoma (RR = 0.50; CI, 0.27-0.90). However, another measure of exposure that included both exposure prior to 1 year and exposure in the past year was associated only with cancer of the lip/tongue (RR = 1.82; CI, 1.02-3.32). No association was observed for lung, bladder, or larynx cancer or multiple myeloma. Analyses limited to men, or stratified by time since health examination, did not distinguish other effects. Self-reported occupational exposure to engine exhaust fumes was not convincingly associated with most cancers in this cohort.

Adolescent↗
PubMed1993

Health care use by frequent marijuana smokers who do not smoke tobacco.

Even though marijuana smoke contains carcinogens and more tar than tobacco smoke and marijuana intoxication has been implicated as a risk factor for injuries, relatively little epidemiologic evidence has identified marijuana use as a risk factor for ill health. This study is the first to examine the health effects of smoking marijuana by comparing the medical experience of "daily" marijuana smokers who never smoked tobacco (n = 452) with a demographically similar group of nonsmokers of either substance (n = 450). Marijuana smoking status was determined during multiphasic health checkups at Kaiser Permanente medical centers between July 1979 and December 1985. Medical records were reviewed for as long as 2 years after the checkups. Frequent marijuana smokers had small increased risks of outpatient visits for respiratory illnesses (relative risk [RR] = 1.19; 95% confidence interval [CI] = 1.01, 1.41), injuries (RR = 1.32; CI = 1.10, 1.57), and other types of illnesses (RR = 1.09; CI = 1.02, 1.16) compared with nonsmokers; their risk of being admitted to a hospital was elevated but not statistically significant (RR = 1.51; CI = 0.93, 2.46). Analyses were adjusted for sex, age, race, education, marital status, and alcohol consumption. Daily marijuana smoking, even in the absence of tobacco, appeared to be associated with an elevated risk of health care use for various health problems.

Adult↗
PubMed1992

Alcohol and mortality.

OBJECTIVE: To study the relation between alcohol intake and mortality in a large ambulatory population with attention to causes of death and differences related to age, sex, race, and baseline risk. DESIGN: Prospective cohort study. SETTING: Prepaid comprehensive health care program facilities in Oakland and San Francisco, California. PARTICIPANTS: Adults (n = 128,934) who supplied data at health evaluations between 1978 and 1985. MEASUREMENTS: Demographic data and health history were supplied using questionnaires. Death was ascertained by an automated linkage system and was individually validated. Relative risk for death at various levels of drinking was calculated by Cox proportional hazards models using lifelong nondrinkers as the reference and controlling for eight covariables. RESULTS: Heavier drinkers were at greater risk for death from noncardiovascular causes (relative risk at greater than or equal to 6 drinks per day compared with no alcohol = 1.6, 95% Cl, 1.3 to 2.0) especially cirrhosis, unnatural death, and tobacco-related cancers. This alcohol-associated risk was higher in women (relative risk for death from all causes at greater than or equal to 6 drinks per day = 2.2; Cl, 1.4 to 3.8) and younger persons (for persons less than 50 years of age, relative risk for death from all causes at greater than or equal to 6 drinks per day = 1.9; Cl, 1.3 to 2.9). Lighter drinkers were at lower risk for death from cardiovascular disease, especially coronary heart disease (relative risk at 1 to 2 drinks per day = 0.7; Cl, 0.6 to 0.9), independent of baseline risk, with the greatest reduction of risk in older persons. Lighter drinkers over 60 years of age also had a slightly lower risk for noncardiovascular death, but this finding was not independent of baseline coronary heart disease risk. CONCLUSIONS: Women and younger persons appear more susceptible to the increased mortality risk of heavy drinking. The reduced cardiovascular risk of lighter drinkers is more pronounced in older persons. Lower coronary disease prevalence may reduce the noncardiovascular mortality risk of lighter drinkers.

Adult↗
PubMed1992

A case-control study of screening sigmoidoscopy and mortality from colorectal cancer.

BACKGROUND: The efficacy of sigmoidoscopic screening in reducing mortality from colorectal cancer remains uncertain. A randomized trial would be ideal for clarifying this issue but is very difficult to conduct. Case-control studies provide an alternative method of estimating the efficacy of screening sigmoidoscopy. METHODS: Using data on the 261 members of the Kaiser Permanente Medical Care Program who died of cancer of the rectum or distal colon from 1971 to 1988, we examined the use of screening by rigid sigmoidoscopy during the 10 years before the diagnosis and compared it with the use of screening in 868 control subjects matched with the case subjects for age and sex. RESULTS: Only 8.8 percent of the case subjects had undergone screening by sigmoidoscopy, as compared with 24.2 percent of the controls (matched odds ratio, 0.30; 95 percent confidence interval, 0.19 to 0.48). Adjustment for potential confounding factors increased the odds ratio to 0.41 (95 percent confidence interval, 0.25 to 0.69). The negative association was as strong when the most recent sigmoidoscopy was 9 to 10 years before diagnosis as it was when examinations were more recent. By contrast, for 268 subjects with fatal colon cancer above the reach of the sigmoidoscope and for 268 controls, the adjusted odds ratio was 0.96 (95 percent confidence interval, 0.61 to 1.50). The specificity of the negative association for cancer within the reach of the sigmoidoscope is consistent with a true efficacy of screening rather than a confounding by unmeasured selection factors. CONCLUSIONS: Screening by sigmoidoscopy can reduce mortality from cancer of the rectum and distal colon. A screening once every 10 years may be nearly as efficacious as more frequent screening.

Aged↗
PubMed1992

Leukemia, lymphoma, and multiple myeloma following selected medical conditions.

The role of selected prior medical conditions in the etiology of hematopoietic malignancies was examined in a case-control study of members of two regional branches of the Kaiser Permanente Medical Care Program (USA). Past history of chronic infectious, autoimmune, allergic, and musculoskeletal disorders was abstracted from medical records for leukemia (n = 299), non-Hodgkin's lymphoma (NHL, n = 100), and multiple myeloma (n = 175) cases and matched controls (n = 787). Little difference was found between cases and controls for most of the chronic conditions evaluated, including sinusitis, carbuncles, urinary tract infections, pelvic infections, herpes zoster, asthma, rheumatoid arthritis, psoriasis, bursitis, and gout. Only three statistically significant elevated risks were found, i.e., with combined disc disease myeloma among patients with prior eczema and disk and other musculoskeletal conditions, and NHL following tuberculosis. Only two of these associations showed consistent patterns by sex and geographic region (myeloma with eczema and with musculoskeletal conditions). While prior history of eczema and musculoskeletal conditions may slightly increase risk of myeloma, this study provided little if any support for an association of chronic infectious, autoimmune, allergic, and musculoskeletal conditions with subsequent occurrence of the leukemias or NHL. Additionally, these data did not support a role for chronic antigenic stimulation, as defined in previous epidemiologic studies, in the etiology of hematopoietic malignancies.

Aged↗
PubMed1992

Forced expiratory volume (1 second) and lung cancer incidence and mortality.

We evaluated the relation between forced expiratory volume in 1 second (FEV1) and lung cancer incidence and mortality among members of the Kaiser Permanente Medical Care Program who took a multiphasic health checkup. FEV1 was inversely related to risk of lung cancer among former and current smokers, but not related among never-smokers. We observed a decreased risk of lung cancer mortality only in the higher quintiles of FEV1 in current smokers among men, but not in women. FEV1 appears to be associated with lung cancer as a physiologic marker for smoking-induced pulmonary damage.

Adolescent↗
PubMed1992

Misclassification of smoking status in the CARDIA study: a comparison of self-report with serum cotinine levels.

BACKGROUND: Although widely used in epidemiological studies, self-report has been shown to underestimate the prevalence of cigarette smoking in some populations. METHODS: In the CARDIA study, self-report of cigarette smoking was validated against a biochemical marker of nicotine uptake, serum cotinine. RESULTS: The prevalence of smoking was slightly lower when defined by self-report (30.9%) than when defined by cotinine levels equal to or greater than 14 ng/mL (32.2%, P less than .05). The misclassification rate (proportion of reported nonsmokers with cotinine levels of at least 14 ng/mL) was 4.2% and was significantly higher among subjects who were Black, had a high school education or less, or were reported former smokers. Possible reasons for misclassification include reporting error, environmental tobacco smoke, and an inappropriate cutoff point for delineation of smoking status. Using self-report as the gold standard, the cotinine cutoff points that maximized sensitivity and specificity were 14, 9, and 15 ng/mL for all, White, and Black subjects, respectively. The misclassification rate remained significantly higher in Black than in White subjects using these race-specific criteria. CONCLUSIONS: Misclassification of cigarette smoking by self-report was low in these young adults; however, within certain race/education groups, self-report may underestimate smoking prevalence by up to 4%.

Adolescent↗
PubMed1991

Helicobacter pylori infection and the risk of gastric carcinoma.

BACKGROUND: Infection with Helicobacter pylori has been linked with chronic atrophic gastritis, an inflammatory precursor of gastric adenocarcinoma. In a nested case-control study, we explored whether H. pylori infection increases the risk of gastric carcinoma. METHODS: From a cohort of 128,992 persons followed since the mid-1960s at a health maintenance organization, 186 patients with gastric carcinoma were selected as case patients and were matched according to age, sex, and race with 186 control subjects without gastric carcinoma. Stored serum samples collected during the 1960s were tested for IgG antibodies to H. pylori by enzyme-linked immunosorbent assay. Data on cigarette use, blood group, ulcer disease, and gastric surgery were obtained from questionnaires administered at enrollment. Tissue sections and pathology reports were reviewed to confirm the histologic results. RESULTS: The mean time between serum collection and the diagnosis of gastric carcinoma was 14.2 years. Of the 109 patients with confirmed gastric adenocarcinoma (excluding tumors of the gastroesophageal junction), 84 percent had been infected previously with H. pylori, as compared with 61 percent of the matched control subjects (odds ratio, 3.6; 95 percent confidence interval, 1.8 to 7.3). Tumors of the gastroesophageal junction were not linked to H. pylori infection, nor were tumors in the gastric cardia. H. pylori was a particularly strong risk factor for stomach cancer in women (odds ratio, 18) and blacks (odds ratio, 9). A history of gastric surgery was independently associated with the development of cancer (odds ratio, 17; P = 0.03), but a history of peptic ulcer disease was negatively associated with subsequent gastric carcinoma (odds ratio, 0.2; P = 0.02). Neither blood group nor smoking history affected risk. CONCLUSIONS: Infection with H. pylori is associated with an increased risk of gastric adenocarcinoma and may be a cofactor in the pathogenesis of this malignant condition.

Adenocarcinoma↗
PubMed1991

Case-control study of screening for prostatic cancer by digital rectal examinations.

Although commonly thought to be an effective method of screening for prostatic cancer, digital rectal examinations have yet to be shown by controlled study to help prevent advanced forms of this disease. 139 men with metastatic (stage D) prostatic cancer (cases) were compared with an equal number of matched men free of this condition (controls), with respect to rectal examinations recorded in the medical records up to, on average, 23 years before the cases' initial diagnosis of prostatic cancer. Cases and controls were members of a large health maintenance organisation in northern California. In the 10 years before initial diagnosis (excluding the last three months) the average number of examinations for routine screening (2.45 vs 2.52) or to evaluate intestinal or rectal symptoms (0.44 in both) were similar in cases and controls, respectively. After adjustment for racial differences, the relative risk of metastatic prostatic cancer for men with one or more screening rectal examinations compared with men with none was 0.9 with a 95% confidence interval of 0.5-1.7. Screening by routine digital rectal examination appears to have little if any effect in preventing metastatic prostatic cancer. If there is a small benefit, it will be difficult to demonstrate by conventional epidemiological study.

Adult↗
PubMed1991

Diagnostic x-ray procedures and risk of leukemia, lymphoma, and multiple myeloma.

Exposure to diagnostic x-rays and the risk of leukemia, non-Hodgkin's lymphoma (NHL), and multiple myeloma were studied within two prepaid health plans. Adult patients with leukemia (n = 565), NHL (n = 318), and multiple myeloma (n = 208) were matched to controls (n = 1390), and over 25,000 x-ray procedures were abstracted from medical records. Dose response was evaluated by assigning each x-ray procedure a score based on estimated bone marrow dose. X-ray exposure was not associated with chronic lymphocytic leukemia, one of the few malignant conditions never linked to radiation (relative risk [RR], 0.66). For all other forms of leukemia combined (n = 358), there was a slight elevation in risk (RR, 1.17) but no evidence of a dose-response relationship when x-ray procedures near the time of diagnosis were excluded. Similarly, patients with NHL were exposed to diagnostic x-ray procedures more often than controls (RR, 1.32), but the RR fell to 0.99 when the exposure to diagnostic x-ray procedures within 2 years of diagnosis was ignored. For multiple myeloma, overall risk was not significantly high (RR, 1.14), but there was consistent evidence of increasing risk with increasing numbers of diagnostic x-ray procedures. These data suggest that persons with leukemia and NHL undergo x-ray procedures frequently just prior to diagnosis for conditions related to the development or natural history of their disease. There was little evidence that diagnostic x-ray procedures were causally associated with leukemia or NHL. The risk for multiple myeloma, however, was increased among those patients who were frequently exposed to x-rays.

Adult↗