Associations Between Hypothyroidism and Subclinical Atherosclerosis Among Male and Female Patients Without Clinical Disease Referred to Computed Tomography.

OBJECTIVES: Hypothyroidism is recognized as a risk factor for coronary artery disease (CAD). However, reports are conflicting when the results are stratified by sex and the underlying risk of CAD. We examine the sex-specific associations of hypothyroidism with coronary calcification and plaques. METHODS: Retrospective cross-sectional study was conducted among adult patients referred to (64 multidetector spiral) computed tomography. Those with pre-existing CAD were excluded. Hypothyroidism was defined as thyroid-stimulating hormone ≥ 4.5 mU/L. Plaques were determined based on quantification of coronary calcium and coronary computed tomography angiography. RESULTS: A total of 2499 patients (1544 male and 955 female) were included. The prevalence of hypothyroidism was significantly higher in female than in male patients (18.0% vs 12.9%, P < .001), in all patients and those <65 years. Hypothyroidism in male patients was significantly associated with higher coronary calcium score > 0, higher coronary calcium score groups, and both soft and calcified plaques (P = .027, P = .032, P = .005, and P = .017, respectively). After adjusting for traditional coronary risk factors, the higher risk in male patients remained significant for coronary plaque but not for coronary calcium score >0 (odds ratios and CIs were 1.77, 1.08-2.90, P = .023 and .98, 0.63-1.52, P = .925, respectively). On the other hand, hypothyroidism in female patients was not significantly associated with coronary calcification nor plaques in both univariate and multivariate analyses. CONCLUSIONS: There are sex-specific differences in the association of hypothyroidism with subclinical atherosclerosis. The higher risk of coronary plaques but not calcification in male patients was independent of traditional coronary risk factors. The lack of associations in female patients may be related to lower underlying risk of CAD.

Association of blood lipids with coronary artery plaque among Saudi patients referred to computed tomography.

BACKGROUND: Blood lipids are strong risk factors for the progression of atherosclerotic plaques. However, data on gender-specific associations are limited. OBJECTIVES: To examine gender-specific associations of coronary plaque with blood lipids among a large sample of Saudi patients without CAD. METHODS: Retrospective cross-sectional study was conducted among adult patients referred to (64 multidetector spiral) computed tomography (CT) for standard indications at the Prince Sultan Cardiac Centre (Riyadh, Saudi Arabia) between July 2007 and December 2017. Those with pre-existing CAD were excluded. Plaques were determined based on quantification of coronary calcium and Coronary CT angiography. RESULTS: A total 2421 patients (1498 males and 923 females) were included. The prevalence of any plaque was 36.6% with higher burden in males than females (41.3% versus 28.9%, p < 0.001). Approximately 78.9% of all plaques were calcified. Blood lipids (mmol/L) were 4.75 ± 1.14 for total cholesterol, 2.90 ± 0.96 for LDL cholesterol, 1.20 ± 0.36 for HDL cholesterol, and 1.64 ± 1.09 for triglycerides. Males had significantly higher triglycerides and lower HDL cholesterol compared with females. In adjusted models in males and all patients, soft and/or calcified plaques were significantly associated with lower HDL cholesterol and higher triglycerides. In females, the only significant association was between soft plaques and higher triglycerides. CONCLUSIONS: Middle-aged patients without clinical CAD in Saudi Arabia have a high burden of plaques, specially calcified ones. The findings may impact the use of lipid lowering mediations, by underscoring the importance of assessing the risk of CAD in patients without clinical CAD even in case of lack of coronary calcification.

Distributions and burden of coronary calcium in asymptomatic Saudi patients referred to computed tomography.

BACKGROUND: Unlike Western and Asian populations, the prevalence and severity of coronary artery calcification (CAC) have not been adequately examined in Saudi Arabia and other nearby Arab Gulf countries. OBJECTIVES: To estimate the age and gender specific percentiles of coronary calcium score (CCS) and to study the severity of CAC in relation to patient risk in a large sample of asymptomatic Saudi patients. METHODS: Retrospective cross-sectional study was conducted between July 2007 and December 2017 at a large Cardiac Centre in Riyadh, Saudi Arabia. The target was adult patients without pre-existing CAD referred to (64 multidetector spiral) computed tomography for standard indications. RESULTS: A total 2863 patients were included in the current analysis. The 90th percentile of CCS was 95.0 in males compared with 53.2 in females and was 823.95 in patients aged ≥ 75 years compared with zero in patients < 40 years. Extensive CAC (CCS > 400) were 3.1% in males compared with 1.6% in females and 14.0% in patients aged ≥ 75 years compared with 0.0% in patients < 40 years. CCS was steadily higher with increasing European systematic coronary risk evaluation; 3.1 ± 22.5 in mild risk, 37.1 ± 201.9 in moderate risk, 116.1 ± 256.1 in high risk, and 131.0 ± 222.0 in very high risk. CONCLUSIONS: As expected, the findings confirm the higher burden of CAC in males, older age, and higher CAD risk. The burden of CAC in current patients is much lower than reported in US and other Western patients. Local cardiologist should consider using local rather than US percentiles of CCS.