Children with lower respiratory tract infections and serum 25-hydroxyvitamin D levels: A case-control study.

Background: Pneumonia is the leading cause of death in children under age of 5 years worldwide. The role of vitamin D in respiratory infections including pneumonia is unclear; therefore, we aimed to determine if children with lower respiratory tract infections had low serum 25-hydroxyvitamin D .

Methods: We performed a case-control study of children ages 3-60 months from the Guatemala City metropolitan area, hospitalized with community-acquired pneumonia between September and December 2012.

Statin Therapy and Risk of Acute Memory Impairment.

Importance: Reports on the association between statins and memory impairment are inconsistent.

Objective: To assess whether statin users show acute decline in memory compared with nonusers and with users of nonstatin lipid-lowering drugs (LLDs).

Design, Setting, And Participants: Using The Health Improvement Network database during January 13, 1987, through December 16, 2013, a retrospective cohort study compared 482,543 statin users with 2 control groups: 482,543 matched nonusers of any LLDs and all 26,484 users of nonstatin LLDs.

Detecting pregnancy use of non-hormonal category X medications in electronic medical records.

Objectives: To determine whether a rule-based algorithm applied to an outpatient electronic medical record (EMR) can identify patients who are pregnant and prescribed medications proved to cause birth defects.

Design: A descriptive study using the University of Pennsylvania Health System outpatient EMR to simulate a prospective algorithm to identify exposures during pregnancy to category X medications, soon enough to intervene and potentially prevent the exposure. A subsequent post-hoc algorithm was also tested, working backwards from pregnancy endpoints, to search for possible exposures that should have been detected.

Evaluating health information technology's clinical effects.

In 2009 the federal government appropriated $34 billion in stimulus-related funding to promote the "meaningful use" of health information technology among Medicare and Medicaid providers and hospitals. One of the key elements of this technology is the adoption of computerized physician order entry (CPOE) systems for inpatient drug prescribing. The potential for CPOE to improve prescribing patterns and prevent adverse events is large, and as yet, unrealized.

Unintended effects of a computerized physician order entry nearly hard-stop alert to prevent a drug interaction: a randomized controlled trial.

Background: The effectiveness of computerized physician order entry (CPOE) systems has been modest, largely because clinicians frequently override electronic alerts.

Methods: To evaluate the effectiveness of a nearly "hard stop" CPOE prescribing alert intended to reduce concomitant orders for warfarin and trimethoprim-sulfamethoxazole, a randomized clinical trial was conducted at 2 academic medical centers in Philadelphia, Pennsylvania. A total of 1981 clinicians were assigned to either an intervention group receiving a nearly hard stop alert or a control group receiving the standard practice.

Randomized clinical trial of a customized electronic alert requiring an affirmative response compared to a control group receiving a commercial passive CPOE alert: NSAID--warfarin co-prescribing as a test case.

Background: Studies that have looked at the effectiveness of computerized decision support systems to prevent drug-drug interactions have reported modest results because of low response by the providers to the automated alerts.

Objective: To evaluate, within an inpatient computerized physician order entry (CPOE) system, the incremental effectiveness of an alert that required a response from the provider, intended as a stronger intervention to prevent concurrent orders of warfarin and non-steroidal anti-inflammatory drugs (NSAIDs).

Design: Randomized clinical trial of 1963 clinicians assigned to either an intervention group receiving a customized electronic alert requiring affirmative response or a control group receiving a commercially available passive alert as part of the CPOE.

Validity of The Health Improvement Network (THIN) for epidemiologic studies of hepatitis C virus infection.

Purpose: Before using computerized databases to study hepatitis C virus (HCV) epidemiology, the validity of the diagnosis must be assessed. We determined the accuracy of HCV diagnostic codes within The Health Improvement Network (THIN), an electronic database containing medical record data from general medical practices in the United Kingdom.

Methods: Patients with initial diagnostic codes for HCV infection and nonspecific viral hepatitis between 2000 and 2007 in the THIN database were identified.

Cancer incidence in The Health Improvement Network.

Background: The utility of electronic medical record databases for clinical research relies on the validity and completeness of the recorded medical diagnoses. This study assessed whether the recorded incidence of cancer among patients in The Health Improvement Network (THIN) database is comparable to that expected in the UK based on national cancer registry data.

Methods: We examined incidence rates of any cancer other than non-melanoma skin cancer and the specific cancers colorectal, lung, pancreas, and lymphoma from 1992 to 2007.

Impact of raloxifene or tamoxifen use on endometrial cancer risk: a population-based case-control study.

Purpose: Raloxifene reduces breast cancer risk in women with osteoporosis, and both tamoxifen and raloxifene prevent breast cancer in high-risk women. However, in vitro, raloxifene does not share the pro-estrogenic effects of tamoxifen on the endometrium. Randomized trials of these agents have provided limited information about endometrial cancer risk in the general population.

Pharmacogenetic modulation of combined hormone replacement therapy by progesterone-metabolism genotypes in postmenopausal breast cancer risk.

Combined hormone replacement therapy (CHRT) containing estrogens and progestins is associated with breast cancer risk. The authors evaluated interactions between CHRT use and progestin metabolism genotypes at CYP3A4 and the progesterone receptor (PGR) and their effects on breast cancer risk using the population-based Women's Insights and Shared Experiences (WISE) Study (1999-2002) of postmenopausal Caucasian women (522 breast cancer cases, 708 controls). The authors observed an elevated risk of ductal tumors in women with 3 or more years of CHRT use and PGR 331A alleles compared with those who had neither factor (odds ratio = 3.

Pairwise combinations of estrogen metabolism genotypes in postmenopausal breast cancer etiology.

Estrogen exposures have been associated with breast cancer risk, and genes involved in estrogen metabolism have been reported to mediate that risk. Our goal was to better understand whether combinations of candidate estrogen metabolism genotypes are associated with breast cancer etiology. A population-based case-control study in three counties of the Philadelphia Metropolitan area was undertaken.

A retrospective case-control study of the use of hormone-related supplements and association with breast cancer.

Hormone-related supplements (HRS), many of which contain phytoestrogens, are widely used to manage menopausal symptoms, yet their relationship with breast cancer risk has generally not been evaluated. We evaluated whether use of HRS was associated with breast cancer risk, using a population-based case-control study in 3 counties of the Philadelphia metropolitan area consisting of 949 breast cancer cases and 1,524 controls. Use of HRS varied significantly by race, with African American women being more likely than European American women to use any herbal preparation (19.

Validation studies of the health improvement network (THIN) database for pharmacoepidemiology research.

Background: The Health Improvement Network (THIN) is a new medical records database that contains records from general practices some of which have or continue to participate in the General Practice Research Database (GPRD) and others that never participated in GPRD. We sought to replicate in THIN well-established associations from the medical literature and to compare results from the GPRD practices to the non-GPRD practices within THIN.

Methods: Using THIN data from 1986-2003, we conducted case-control studies of associations between diseases (e.

Case-control study of postmenopausal hormone replacement therapy and endometrial cancer.

This study evaluated recent inconsistent findings that adding progestins to postmenopausal estrogen replacement therapy protects against endometrial cancer. Using a population-based case-control study, the authors compared 511 endometrial cancer cases aged 50-79 years in the Philadelphia, Pennsylvania, region during 1999-2002 with 1,412 random-digit-dialing controls regarding postmenopausal hormone replacement therapy (HRT) use. Telephone interviews were performed with memory aids mailed in advance.

Estrogen sulfation genes, hormone replacement therapy, and endometrial cancer risk.

Background: Unopposed estrogen replacement therapy is associated with increased risk of endometrial cancer. To investigate the mechanism of this association, we evaluated whether risk of endometrial cancer was associated with the genotypes involved in steroid hormone metabolism and the duration of exogenous hormone use.

Methods: A population-based case-control study in nine counties of the Philadelphia metropolitan area was undertaken with 502 case patients with endometrial cancer and 1326 age- and race-matched control subjects.

Weight gain in the first week of life and overweight in adulthood: a cohort study of European American subjects fed infant formula.

Background: Successful prevention of obesity and related cardiovascular risk factors requires a clear understanding of its determinants over the life course. Rapid infancy weight gain is associated with childhood obesity, whereas low infancy weight is associated with coronary heart disease. Our aim was to identify during which periods in infancy weight gain is associated with adult obesity.

An interview strategy was critical for obtaining valid information on the use of hormone replacement therapy.

Objective: We compared telephone reports of hormone replacement therapy (HRT) use to claims for drugs dispensed.

Study Design And Setting: The study subjects included 106 women who were dispensed HRT and 107 who were not dispensed HRT.

Results: Recall of drug use overall was relatively good (65/79=82.

Participants and refusers in a telephone interview about hormone replacement therapy were equally likely to be taking it.

Objective: To address a major concern in pharmacoepidemiology studies related to whether the characteristics of responders are different from those who refuse to participate.

Study Design And Setting: We compared utilization of postmenopausal hormone replacement therapy (HRT) in women who agreed to participate in a telephone interview on HRT utilization and in women who refused to participate in the telephone interview. Information on HRT utilization among responders and refusers was independently available to us from a claims database (the Healthcare Management Alternatives, HMA, in Philadelphia), showing drugs dispensed to these patients.

Risk of bleeding and hypoprothrombinaemia associated with NMTT side chain antibiotics: using cefoperazone as a test case.

A retrospective cohort study was performed to determine the incidence of hypoprothrombinaemia and bleeding in patients receiving cefoperazone, a third-generation cephalosporin that contains an NMTT side chain. 374 patients receiving cefoperazone from February 1983 to March 1986 at a teaching hospital in Philadelphia were compared with 497 patients receiving either ceftizoxime or cefotaxime during the same period, and with 476 patients receiving ceftazidime from April 1985 to December 1987. Adverse events (any bleeding episodes, decrease in haemoglobin, prolongation of prothrombin time (PT), and prolongation of partial thromboplastin times (PTT)) were evaluated, if occurring during the period from the start of cephalosporin therapy, or the start of therapy with one of the two control drugs, for 14 days after the last date of the first course of therapy were recorded.

Absence of cross-reactivity between sulfonamide antibiotics and sulfonamide nonantibiotics.

Background: The safety of sulfonamide nonantibiotics is unclear in patients with prior allergic reactions to sulfonamide antibiotics.

Methods: We conducted a retrospective cohort study using the General Practice Research Database in the United Kingdom, examining the risk of allergic reactions within 30 days after the receipt of a sulfonamide nonantibiotic. Patients with evidence of prior hypersensitivity after the receipt of a sulfonamide antibiotic were compared with those without such evidence.

Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood.

Context: A large body of evidence documents the role of phytoestrogens in influencing hormone-dependent states. Infants fed soy formula receive high levels of phytoestrogens, in the form of soy isoflavones, during a stage of development at which permanent effects are theoretically possible. However, a paucity of data exists on the long-term effects of infant soy formulas.

Gastrointestinal tract bleeding associated with naproxen sodium vs ibuprofen.

Background: The risk of gastrointestinal tract bleeding requiring hospitalization associated with naproxen sodium was compared with that with ibuprofen, using a prescription database to approximate over-the-counter dosing.

Objective: To evaluate the safety of naproxen sodium.

Methods: A claims database containing Ohio Medicaid data from January 1986 through February 1993 and Michigan Medicaid data from April 1983 through July 1993 was used to compare 101,318 patients dispensed naproxen sodium with 277,601 patients dispensed ibuprofen.

Is cimetidine associated with neutropenia?

Background: Cimetidine is perceived as sufficiently safe that it is being considered for over-the-counter use. However, because of residual concerns about cimetidine-induced neutropenia, a study was conducted to evaluate this association.

Methods: A population-based, case-control study was undertaken using a large database with Medicaid data from six states.

Breast silicone implants and risk of systemic lupus erythematosus.

The uncertain safety of breast implants has been a major controversy of late, both in the lay press and in the scientific literature. A case-control study had been performed in the Philadelphia metropolitan area during 1985-1987 to investigate potential risk factors for systemic lupus erythematosus (SLE). A total of 219 eligible cases who met the American Rheumatism Association criteria for SLE were identified from the medical practices of cooperating rheumatologists in the area; 195 (89%) of these were enrolled in the study.