Biomedical subjects

James McKay

Publications and source records attributed to James McKay.

7 recordsLinked to original sources

PubMed2025

Blood Pressure Lowering and Risk of Cancer: Individual Participant-Level Data Meta-Analysis and Mendelian Randomization Studies.

BACKGROUND: Pharmacologic blood pressure (BP) lowering is typically a lifelong treatment, and both clinicians and patients may have concerns about the long-term use of antihypertensive agents and the risk for cancer. However, evidence from randomized controlled trials (RCTs) regarding the effect of long-term pharmacologic BP lowering on the risk for new-onset cancer is limited, with most knowledge derived from observational studies. OBJECTIVES: The aim of this study was to assess whether long-term BP lowering affects the risk for new-onset cancer, cause-specific cancer death, and selected site-specific cancers. METHODS: Individual-level data from 42 RCTs were pooled using a one-stage individual participant data meta-analysis. The primary outcome was incident cancer of all types, and secondary outcomes were cause-specific cancer death and selected site-specific cancers. Prespecified subgroup analyses were conducted to assess the heterogeneity of the BP-lowering effect by baseline variables and over follow-up time. Cox proportional hazards regression, stratified by trial, was used for the statistical analysis. For site-specific cancers, analyses were complemented with Mendelian randomization, using naturally randomized genetic variants associated with BP lowering to mimic the design of a long-term RCT. RESULTS: Data from 314,016 randomly allocated participants without known cancer at baseline were analyzed. Over a median follow-up of 4 years (Q1-Q3: 3-5 years), 17,954 participants (5.7%) developed cancer, and 4,878 (1.5%) died of cancer. In the individual participant data meta-analysis, no associations were found between reductions in systolic or diastolic BP and cancer risk (HR per 5 mm Hg reduction in systolic BP: 1.03 [95% CI: 0.99-1.06]; HR per 3 mm Hg reduction in diastolic BP: 1.03 [95% CI: 0.98-1.07]). No changes in relative risk for incident cancer were observed over follow-up time, nor was there evidence of heterogeneity in treatment effects across baseline subgroups. No effect on cause-specific cancer death was found. For site-specific cancers, no evidence of an effect was observed, except a possible link with lung cancer risk (HR for systolic BP reduction: 1.17; 99.5% CI: 1.02-1.32). Mendelian randomization studies showed no association between systolic or diastolic BP reduction and site-specific cancers, including overall lung cancer and its subtypes. CONCLUSIONS: Randomized data analysis provided no evidence to indicate that pharmacologic BP lowering has a substantial impact, either increasing or decreasing, on the risk for incident cancer, cause-specific cancer death, or selected site-specific cancers.

epidemiology↗

PubMed2006

The association of sequence variants in DNA repair and cell cycle genes with cancers of the upper aerodigestive tract.

Cancers of the upper aerodigestive tract (UADT), comprising the oral cavity, pharynx, larynx and oesophagus, account for 5.2% of all cancers cases worldwide. The major risk factors, tobacco and alcohol can directly or indirectly generate DNA damage, which if unrepaired can give rise to mutations, unregulated cell growth and apoptosis induction. To clarify the role of DNA repair and cell cycle control proteins in UADT cancer susceptibility, we studied the risk in relation to 28 SNPs in 18 DNA repair enzymes and 9 SNPs in 7 cell cycle control genes. A case-control study was conducted from 2000 to 2002 in six centers from Romania, Poland, Russia, Slovakia and the Czech Republic. Patients diagnosed with squamous cell carcinoma of the UADT (n=811) and controls with a recent diagnosis of diseases unrelated to tobacco and alcohol (n=1083) were recruited. For UADT cancer risk, associations were observed for the homozygous carriers of the variant alleles of MGMT L84F [odds ratio (OR) 2.35, 95% confidence interval (CI) 1.32-4.20], MGMT 171C > T (OR 2.24, 95% CI 1.20-4.17) and OGG1 S326C (OR 2.07, 95% CI 1.15-3.73) whilst three variants were associated with a protective effect (XPA 23G > A, P for trend 0.022, APEX Q51H, P for trend 0.036, CHEK2 intron 9-200T > C, P for trend 0.009). Several other sequence variants showed associations with specific cancers without an overall association with UADT cancer. While some of these associations are consistent with previous studies, we cannot rule out the possibility of false-positive associations. The positive findings should be explored in another large-scale study on UADT cancers.

Adult↗

PubMed2005

A Greek family with a follicular variant of familial papillary thyroid carcinoma: TCO, MNG1, fPTC/PRN, and NMTC1 excluded as susceptibility loci.

The familial form of nonmedullary thyroid carcinoma (FNMTC) has been recognized as a distinct clinical entity and is characterized by multifocality and a more severe phenotype than its sporadic counterpart. The majority of FNMTC pedigrees are small in size, show variable modes of inheritance, and may present with a variety of additional benign thyroid disorders. The existence of marked phenotypic differences between FNMTC families suggests that there is genetic heterogeneity. Recent studies have mapped a susceptibility locus for FNMTC at 2q21. This locus appears particular relevant to families with at least one case of the follicular variant of papillary thyroid cancer (fvPTC). We describe the clinical and pathologic characteristics of a large three-generation fPTC kindred, with two of the four PTC patients presented with the follicular variant of PTC. It is of interest the occurrence of PTC in three siblings within a period of 3 years. In addition, multinodular goiter (MNG) was diagnosed in seven individuals, lymphocytic thyroiditis in four, while one diagnosed with a benign adenoma. From the PTC patients, one had MNG and fvPTC, one MNG, lymphocytic thyroiditis and papillary pattern of PTC, one lymphocytic thyroiditis and fvPTC, and one MNG and papillary pattern of PTC. The inheritance pattern was autosomal dominant with incomplete penetrance and women were affected more frequently than men. Considering all PTC-affected individuals, the limit of detection (LOD) score we got for this family on 2q21 was 0.5. The low LOD score is caused by a PTC patient who does not share the affected haplotype, suggesting that maybe a new locus for PTC predisposition is present in this kindred. Linkage analysis also excluded TCO, MNG, and fPTC/PRN as susceptibility loci to FNMTC in this family.

Adenocarcinoma, Follicular↗

PubMed2004

Allelic loss on chromosomes 2q21 and 19p 13.2 in oxyphilic thyroid tumors.

Hürthle thyroid tumors are characterized by frequent numerical chromosomal aberrations, including aneuploidy or polyploidy, losses and gains of some chromosomal regions and DNA fragmentation. In recent years, great attention has been paid to the combined analysis of morphologic and genetic features of oxyphilic tumors and to the elucidation of their pathogenesis. We analyzed for loss of heterozygosity (LOH) of the candidate regions for TCO (thyroid tumor with cell oxyphilia) and NMTC1 (nonmedullary thyroid carcinoma 1), 2 loci already mapped on chromosomes 19p13.2 and 2q21, respectively. Matched normal and tumor DNA samples from 70 patients with sporadic oxyphilic thyroid tumors and 20 with sporadic follicular tumors were subjected to microsatellite analysis using 10 markers on 19p13.2 and 6 markers on 2q21. This approach led us to the observation of a more significant LOH in oxyphilic than in follicular tumors. Allelic loss in tumor samples was evenly distributed in both 19p13.2 and 2q21 regions, in accordance with the established linkage of TCO and NMTC1 for inherited tumors. In order to investigate the possible contribution of both susceptibility loci in oxyphilic tumors, the family that led to the original mapping of TCO locus was reanalyzed for the markers in the 2q21 region. This led to the exclusion of linkage with the NMTC1 locus and to the refutation of the digenic inheritance hypothesis at least in this family.

Adenocarcinoma↗

PubMed2004

Co-occurring alcohol and cocaine dependence: recent findings from clinical and field studies.

This article represents the proceedings of a symposium held at the 2003 annual meeting of the Research Society on Alcoholism in Ft. Lauderdale, FL. The organizer and chair was Barbara A. Flannery, and the discussant was Raye Z. Litten. The presentations were (1) Examining treatment trajectories of alcohol and cocaine dependent patients, by Jon Morgenstern; (2) Outcomes of alcoholics with and without cocaine dependence in a continuing care study, by James R. McKay; (3) Characteristics of non-treatment seeking cocaine and alcohol dependent African Americans, by Barbara A. Flannery; and (4) Cocaine and alcohol use among sex workers in South Africa, by Wendee M. Wechsberg.

Adult↗

PubMed2003

Services integration and cost-effectiveness.

Alcohol treatment services are increasingly combined with other health and social services to address the needs of multiple-problem clients. Hence, it has been of growing policy interest to find the most effective and the most cost-effective ways of linking these services. This symposium presents some recent studies in this area. The small but growing body of studies in this area has great potential to inform public policy debates.

Alcoholism↗

PubMed2003

Potential barriers to work for substance-abusing women on welfare. Findings from the CASAWORKS for Families pilot demonstration.

AIM: To assess the prevalence and relationship to later employment of potential barriers to work for substance-abusing women on Temporary Assistance to Needy Families (TANF) enrolled in a multiservice welfare-to-work program. DESIGN: A field study with repeated measures and intent-to-treat sampling. INTERVENTION: The CASAWORKS for Families (CWF) was delivered in 11 sites in nine states across the nation and featured integration of substance-abuse treatment and employment and work readiness services. MEASUREMENT: The Addiction Severity Index, supplemented with subject-appropriate questions. SAMPLE: A total of 366 CWF women who completed interviews at program enrollment, and at 6 and 12 months later. FINDINGS: Substance-abusing women on TANF in the CWF program exhibited multiple potential barriers to work at enrollment, averaging 6 out of 14 potential barriers assessed. They reported significantly more obstacles than a general welfare sample of women from the same locales. Few single barriers were significantly related to employment at 12 months. However, the total number of potential barriers to work experienced, particularly at 6 months, was related to employment at 12 months.

Adult↗