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Biomedical subjects

H Jick

Publications and source records attributed to H Jick.

At least 19 recordsLinked to original sources
PubMed1992

Maternal heat exposure and neural tube defects.

OBJECTIVE: To determine if exposure to hot tub, sauna, fever, or electric blanket during early pregnancy was associated with an increased risk for neural tube defects (NTDs). DESIGN: Prospective follow-up study. SETTING: Mostly private obstetric practices, primarily in New England. PARTICIPANTS: A cohort of 23,491 women having serum alpha-fetoprotein screening or an amniocentesis were identified. Complete exposure and outcome information was available for 97% of these women. OUTCOME MEASURES: Relative risks (RRs) were used to compare incidence of NTD in those exposed to heat with those who were not exposed to any heat. Crude RRs were calculated directly from the data. Unconfounded RRs were calculated using logistic regression. RESULTS: Women reporting any heat exposure (sauna, hot tub, fever, or electric blanket) in early pregnancy had a crude risk of their fetuses developing NTD of 1.6 (95% CI [confidence interval], 0.9 to 2.9). Women reporting exposure to sauna, hot tub, or fever in early pregnancy had a crude risk of their fetuses developing NTD 2.2 times that of women without heat exposure (95% CI, 1.2 to 4.1). For hot tub use, the crude RR was 2.9 (95% CI, 1.4 to 6.3); for sauna, 2.6 (95% CI, 0.7 to 10.1); for fever, 1.9 (95% CI, 0.8 to 4.1); and for electric blanket, 1.2 (95% CI, 0.5 to 2.6). Multivariate adjusted RRs for individual heat sources, after controlling for maternal age, folic acid supplements, family history of NTD, and exposure to other heat sources, were for hot tub use, 2.8 (95% CI, 1.2 to 6.5); sauna, 1.8 (95% CI, 0.4 to 7.9); fever, 1.8 (95% CI, 0.8 to 4.1); and electric blanket, 1.2 (95% CI, 0.5 to 2.6). When only hot tub, sauna, and fever were considered and the women's exposure to each tallied, compared with no heat exposure, the RR for NTDs increased from 1.9 (95% CI, 0.9 to 3.7) after one type of heat exposure to 6.2 (95% CI, 2.2 to 17.2) after two types of heat exposure. CONCLUSIONS: Exposure to heat in the form of hot tub, sauna, or fever in the first trimester of pregnancy was associated with an increased risk for NTDs. Hot tub exposure appeared to have the strongest effect of any single heat exposure. Exposure to electric blanket was not materially associated with increased risk for NTDs.

Cohort Studies↗
PubMed1992

Maternal zinc and fetal neural tube defects.

Among the factors implicated in the heterogeneous etiology of neural tube defects (NTDs) is the trace element zinc (Zn). In a case-control study, we collected midtrimester maternal toenail samples for multiple trace element analyses, including Zn, which were assayed by neutron activation analysis. We studied 17 women with NTD offspring and 1,787 controls. The crude OR for NTD comparing Zn values greater than normal range to normal Zn values was 3.2 (95% CI 1.1,9.7). These results were not materially affected when adjustment was made for folic acid supplementation. An overall increased risk for NTD associated with increasing toenail Zn was also evident. A matched subset of 17 cases and 73 controls yielded a crude OR of 3.1 (95% CI 0.9,10.3) when cases with elevated Zn (greater than or equal to 120 ppm) were compared to those with normal Zn. Matched analyses controlling for folic acid supplements, family history of NTD, assay batch, age of mother and year of delivery yielded an OR of 5.0 (95% CI 1.1,21.6). This study reveals an association between increased toenail Zn in the second trimester of pregnancy and the risk of having a child with an NTD. Whether Zn sequestration has resulted in relative Zn deficiency at the site of neural tube closure remains uncertain.

Case-Control Studies↗
PubMed1992

Urinary tract infections and estrogen use in older women.

OBJECTIVE: To examine the relationship between exogenous estrogen use and risk of clinically diagnosed urinary tract infection (UTI) in older women. DESIGN: A case-control study. SETTING: Two hundred seventy-six general practices. PATIENTS: Cases (n = 3,616) were women, age 50-69 years, with a first recorded UTI in the calendar years 1989 or 1990. Controls (n = 19,162) were matched for age and practice. MAIN OUTCOME MEASURE: Clinical diagnosis of UTI. RESULTS: Women using estrogens for greater than or equal to 1 year had an increased risk of being diagnosed with a UTI compared to non-users, crude odds ratio (OR) 1.9 (95% CI 1.5-2.2). All of this excess risk was observed in women with intact uteri, OR 2.1 (CI 1.7-2.7). Hysterectomized women had no increased risk, OR 1.1 (CI 0.8-1.5). Controlling for diabetes, neurologic deficit, atrophic vaginitis, incontinence, and age did not affect the observed associations. CONCLUSION: Estrogen use is associated with an increased risk of UTI in older women with intact uteri but not in hysterectomized women. This observed differential effect on women with or without uteri may be explained by prescribing biases between these two groups of women, but we lack any evidence to support this conclusion over several alternative possibilities.

Age Factors↗
PubMed1992

Comparison of frequencies of suicidal tendencies among patients receiving fluoxetine, lofepramine, mianserin, or trazodone.

To evaluate whether fluoxetine causes an important increased risk of suicidal behavior, we compared the frequency of attempted suicide, suicidal ideation, and aggressive behavior in persons who received fluoxetine, lofepramine, mianserin, and trazodone, based on information available on general practitioners' computers provided by Value Added Medical Products, Ltd. The frequency of these events was higher in fluoxetine users in the year prior to first treatment than in users of the other three antidepressants. The frequency of these events in the 90 days after the study drug was started was similar for the users of all four drugs. These data indicate that fluoxetine does not directly cause suicidal behavior at a substantially higher frequency than do lofepramine, mianserin, and trazodone.

Adolescent↗
PubMed1992

Antidepressant drugs and suicide.

The current study provides estimated rates of suicide among users of antidepressant drugs. The data were derived from two population-based data resources: United Kingdom general practitioners using computers provided by Value Added Medical Products, Ltd., and Group Health Cooperative of Puget Sound. The results apply specifically to these populations. The overall rates of suicide in ever users of the study drugs usually used to treat depression were 6.5 x 10(-4) person-years in persons present in the U.K. resource and 5.1 x 10(-4) person-years in members of The Puget Sound group. Rates of suicide among users of particular antidepressant drugs varied somewhat, but the rates were consistent with biologic variability, with the possible exception of rates for mianserin (based on 4 exposed cases), which were higher than rates for other antidepressants. Consistent findings were (1) suicide rates are substantially higher in men than in women, and (2) the use of firearms as a mode of suicide is common in the northwest United States and uncommon in the United Kingdom.

Adult↗
PubMed1992

Antidepressants and convulsions.

We reviewed available computer records and clinical charts in an estimated 42,000 recipients of antidepressant drugs. The study was restricted to persons with no known condition predisposing to convulsions. Only 16 study subjects developed a convulsive disorder that we judged could have been caused by an antidepressant. We conclude that the frequency of convulsions caused by these drugs used at usual prescribed doses in the settings studied is substantially less than one per 1,000 recipients who have no conditions predisposing to convulsions.

Adult↗
PubMed1992

Liver disease associated with diclofenac, naproxen, and piroxicam.

Based on information derived from computers used by general practitioners in the United Kingdom, we identified all patients with any recorded diagnosis of a liver disorder within 90 days of a prior prescription for diclofenac, naproxen, or piroxicam, three nonsteroidal antiinflammatory drugs (NSAIDs). The follow-up cohort consisted of 102,644 persons who used one or more of these drugs. A case history was requested from the physician to provide a description of the liver disorder and its relation to NSAID exposure. One case of clinically important liver disease was likely to have been caused by a study drug and another appeared to be caused by use of numerous NSAIDs. In 10 additional patients a causal connection between a study NSAID and the liver disorder seemed unlikely but could not be fully ruled out. We conclude that serious liver disease caused by diclofenac, naproxen, or piroxicam appears to be uncommon.

Adolescent↗
PubMed1991

Validation of information recorded on general practitioner based computerised data resource in the United Kingdom.

OBJECTIVE: To determine the extent of agreement between clinical information recorded on surgery computers of selected general practitioners and similar information in manual records of letters received from hospital consultants and kept in the general practitioners' files. DESIGN: Hospital consultants' letters in the manual records of selected general practitioners were photocopied and the consultants' clinical diagnoses were compared with diagnoses recorded on computer. SETTING: General practices in the United Kingdom using computers provided by VAMP Health for recording clinical information. SUBJECTS: 2491 patients who received one of three non-steroidal anti-inflammatory drugs and who attended 58 practices whose computer recorded data were considered after a preliminary review to be of satisfactory quality. RESULTS: Among 1191 patients for whom consultants' letters were forwarded a clinical diagnosis reflecting the diagnosis noted on a consultant letter was present on the computer record for 1038 (87%). CONCLUSION: Clinical information available on the computer records of the general practitioners who participated in this study is satisfactory for many clinical studies.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1991

Exposure to phenothiazine drugs and risk of cataract.

Clinical reports have indicated an increased risk of ocular opacities in users of phenothiazine drugs, and some recent epidemiologic studies have found an association between cataract and a history of tranquilizer use. To examine the effects of major tranquilizers (phenothiazines and haloperidol) on the risk of cataract extraction, while controlling for suspected risk factors such as diabetes and steroid use, a matched cohort study was performed using information from a large health maintenance organization in Seattle, Wash. The use of either antipsychotic or other phenothiazine drugs increased the risk of cataract extraction by roughly 3.5 times in individuals who were both current users and were exposed some time in the 2 to 5 years prior to their extraction. Risk was also increased in individuals with prior use of antidiabetic agents, systemic steroids, and benzodiazepines. Contrary to some prior reports, there was no elevated risk associated with use of antihypertensives, and there was no protective effect for aspirin, acetaminophen, or ibuprofen.

Aged↗
PubMed1991

Renal parenchymal disease related to over-the-counter analgesic use.

The occurrence of parenchymal renal disease has been attributed in many case reports to heavy use of over-the-counter (OTC) analgesics. To quantify this putative relationship, we carried out a comprehensive case history review of newly diagnosed parenchymal renal disease requiring hospitalization among patients who ever used acetaminophen, aspirin, or ibuprofen, at Group Health Cooperative of Puget Sound. During the 6-year period 1984-1989, 17 cases of newly diagnosed, unexplained renal disease were identified among the 378,769 users of OTC analgesics, among whom 26,931 filled at least 20 prescriptions for the analgesics studied. Six of the 17 were possibly attributable to outpatient drug use. Of these, OTC analgesics were suspected clinically as a possible causal factor in two, but in both patients other causes seemed equally likely. We did not find any patients with anatomic or pathologic findings associated with analgesic nephropathy. We conclude that parenchymal renal disease attributable to OTC analgesic use and requiring hospitalization is a rare occurrence.

Adult↗
PubMed1991

An observational study of isotretinoin recipients treated for acne in a health maintenance organization.

From September 1982 to June 1987, all members (N = 513) of the Group Health Cooperative of Puget Sound, Seattle, Wash, who were prescribed isotretinoin for acne were observed throughout the first 4- to 5-month course of therapy for effectiveness and adverse effects. The highest rates of use were among male subjects aged 15 to 24 years. Excluding 47 subjects whose prescriptions were stopped because of noncompliance or who left the care of Group Health Cooperative physicians, 39 (8.4%) of the remaining 466 discontinued taking the drug because of the following adverse effects: mucous/skin/musculoskeletal effects (17); elevated triglyceride levels (eight); headaches (five); increased liver enzyme levels (three); amenorrhea (two); and other (four). One subject, excluded from the 466 because of noncompliance, became pregnant while using medication from a previous prescription and had a therapeutic abortion; she was not under the care of a physician at the time of pregnancy. Most subjects (97%) developed a mucocutaneous symptom, and 42% developed musculoskeletal symptoms. Moderate elevations in liver enzyme levels developed in six (1.8%) of 341 subjects with normal baseline values. Of 389 subjects with normal baseline triglyceride values (less than 2.25 mmol/L), nine (2.3%) developed moderate elevations (4.5 to 9.0 mmol/L), and one (0.3%) developed a severe elevation (greater than or equal to 9.0 mmol/L). Of 24 subjects with elevated baseline triglyceride levels, three (12.5%) developed moderate elevations. Of an additional 53 subjects whose baseline serum triglyceride levels were not determined, two developed elevations during therapy, one up to 13.4 mmol/L. Subjects who were overweight or had elevated baseline serum triglyceride values had an increased risk of developing elevations in triglyceride levels during therapy (odds ratio, 6.0; 95% confidence interval, 1.6 to 22.0; and odds ratio, 4.35; 95% confidence interval, 0.9 to 20.2, respectively). Acne was improved for at least 94.0% of subjects.

Acne Vulgaris↗
PubMed1990

Use of replacement estrogens and the risk of myocardial infarction.

We evaluated the relation between postmenopausal estrogen use and the risk of first-time myocardial infarction using both cohort and nested case-control analyses for data derived from a large health maintenance organization. The study population comprised all women aged 50 to 64 years who were members of the Group Health Cooperative of Puget Sound during the years 1978-1984. In the cohort analysis of 120 cases of first-time myocardial infarction that occurred during 17,513 woman-years at risk among current users and 110,971 woman-years at risk among nonusers of replacement estrogens, the relative incidence of myocardial infarction among current users compared with nonusers, adjusted for age and calendar year, was 0.7 (95% confidence interval 0.4-1.3). This small inverse relation between myocardial infarction and current use of replacement estrogens remained unchanged after adjustment in the case-control study for previous prescription of diuretics and antiarhythmic, antihypertensive, and antidiabetic drugs. These data are consistent with previous observations that estrogen replacement therapy causes a small reduction in the risk of hospitalization for myocardial infarction, and incompatible with any large increase in the risk of myocardial infarction in users of replacement estrogen.

Case-Control Studies↗
PubMed1990

The relationship of oral contraceptive use to rheumatoid arthritis.

Current use of oral contraceptives among 71 women aged 17 to 45 diagnosed for the first time as having definite or probable rheumatoid arthritis at Group Health Cooperative of Puget Sound was compared with oral contraceptive use among matched controls. Twenty-three percent of cases and 13% of controls were current users of oral contraceptives at the index date (relative risk estimate = 2.0, 95% CI = 0.97-4.21). We conclude that current oral contraceptive use was not protective against the development of rheumatoid arthritis in this population.

Adolescent↗
PubMed1990

Cimetidine use and gastric cancer.

We conducted a case-control study at Group Health Cooperative of Puget Sound to investigate the relation between long-term cimetidine use and gastric cancer. Five of 99 cases of gastric cancer were exposed to cimetidine at least two years before diagnosis, whereas nine of 365 controls (selected from among users of the Group Health Cooperative pharmacy, matched on age, sex, and first year of pharmacy use) were similarly exposed. The odds ratio comparing users with nonusers was 2.3 (95% CI = 0.8-6.9). The odds ratio comparing users of antacids with nonusers was similar, 1.9 (95% CI = 1.0-3.7). Although a causal relation between gastric cancer and cimetidine is possible, the similarity of the findings for cimetidine and antacids lends support to other explanations.

Adenocarcinoma↗
PubMed1990

A comparison of the risk of hypoglycemia between users of human and animal insulins. 1. Experience in the United Kingdom.

In a case-control study of 121 young insulin-dependent diabetics diagnosed as having an episode of hypoglycemia, the relative risk estimate comparing human with animal insulins was 0.8 (95% confidence interval 0.4, 1.6) controlling for age, general practice, and calendar time. We conclude that in this study population derived from general practices in the United Kingdom, the risk of hypoglycemia was no higher in users of human insulin than it was in users of animal insulins.

Adolescent↗