Metabolic Syndrome Over 4 Years Before the Onset of Cardiovascular Disease - Nested Case-Control Study

Mediation of the association between depression and coronary heart disease by metabolic syndrome components

BACKGROUND

Depression is associated with incident coronary heart disease (CHD) via a pathway that may be causal, but the mechanisms underlying this association are unclear. We assessed the extent to which metabolic syndrome (MetS) and its components (i.e., elevated waist circumference, low high-density lipoprotein [HDL] cholesterol, elevated triglycerides, elevated blood pressure, and elevated fasting plasma glucose) may mediate this association.

METHODS

Data were Framingham Heart Study Research Materials obtained from the National Heart, Lung, and Blood Institute (NHLBI) Biologic Specimen and Data Repository Information Coordinating Center. We used Cox proportional hazards regression to estimate adjusted hazard ratios (aHR) representing the total effect (aHRTE) of probable depression, measured via the Centers for Epidemiological Studies - Depression scale, on incident CHD over approximately 18 years. Using inverse odds ratio weighting, we decomposed this estimate into natural direct effects (aHRNDE) and natural indirect effects (aHRNIE) through potential mediators (measured approximately three years after depression).

RESULTS

Probable depression was associated with incident CHD (aHRTE=1.45, 95% confidence interval [CI]: 0.93, 2.25), and elevated waist circumference partially mediated this association (aHRNDE=1.34, 95% CI: 0.76-2.32; aHRNIE=1.08, 95% CI: 0.63-1.91). We did not find evidence of additional mediation by additional MetS components.

CONCLUSIONS

Elevated waist circumference appears to play a role in the association between depression and CHD.

Metabolic syndrome and the risk of severe cancer events: a longitudinal study in Japanese workers

BACKGROUND

Metabolic syndrome (MetS) is associated with cancer risk; however, little is known regarding its relationship with the risk of cancer-related premature death and long-term sick leave (LTSL), which can lead to a substantial loss in working years. The present study aimed to quantify the all-site and site-specific associations between MetS and the risk of severe cancer events (a composite outcome of LTSL and mortality due to cancer) in a large working population in Japan.

METHODS

We recruited 70,875 workers (59,950 men and 10,925 women), aged 20-59 years, who attended health check-ups in 2011 (10 companies) and 2014 (2 companies). All workers underwent follow up for severe cancer events until March 31, 2020. MetS was defined in accordance with the Joint Interim Statement. Cox regression models were used to quantify the association between baseline MetS and severe cancer events.

RESULTS

During 427,379 person-years of follow-up, 523 participants experienced the outcome consisting of 493 LTSLs of which 124 eventually resulted in death, and 30 deaths without taking LTSL. The adjusted hazard ratios (HR) (95% confidence intervals [CI]) for composite severe events due to all-site, obesity-related, and non-obesity-related cancer among those with vs. without MetS were 1.26 (1.03, 1.55), 1.37 (1.04, 1.82), and 1.15 (0.84, 1.56), respectively. In cancer site-specific analyses, MetS was associated with an increased risk of severe events due to pancreatic cancer (HR, 2.06; 95% CI, 0.99-4.26). When mortality was treated solely as the endpoint, the association was significant for all-site (HR, 1.58; 95% CI, 1.10-2.26), and obesity-related (HR, 1.59; 95% CI, 1.00-2.54) cancer. Additionally, a greater number of MetS components was associated with a greater risk of both severe cancer events and cancer-related mortality (P trend < 0.05).

CONCLUSION

Among Japanese workers, MetS was associated with an increased risk of severe cancer events, especially those due to obesity-linked cancer.

Metabolic syndrome and the increased risk of medically-certified long-term sickness absence: a prospective analysis among Japanese workers

BACKGROUND

Metabolic syndrome (MetS) has been associated with various chronic diseases which may lead to long-term sickness absence (LTSA), but there is lacking information on the direct association between MetS and LTSA. The present study aimed to investigate the all-cause and cause-specific associations between MetS and the risk of medically-certified LTSA among Japanese workers.

METHOD

We recruited 67,403 workers (57,276 men and 10,127 women), aged 20-59 years, of 13 companies in Japan, during their health check-ups in 2011 (11 companies) and 2014 (2 companies), and followed them up for LTSA events (≥ 30 consecutive days) until March 31, 2020. MetS was defined according to the Joint Interim Statement. A Cox proportional hazards regression model was used to estimate hazard ratio (HR) and its 95% confidence interval (CI) for LTSA associated with MetS and its components.

RESULTS

During 408,324 person-years of follow-up, 2,915 workers experienced LTSA. The adjusted HR for all-cause LTSA was 1.54 (95% CI, 1.41-1.68) among those with vs without MetS. In cause-specific analysis, HRs associated with MetS significantly increased for LTSA due to overall physical disorders (1.76), cardiovascular diseases (3.16), diseases of the musculoskeletal system and connective tissue (2.01), cancers (1.24), obesity-related cancers (1.35), mental, behavioral and neurodevelopmental disorders (1.28), reaction to severe stress and adjustment disorders (1.46) and external causes (1.46). The number of MetS components were also significantly associated with increased LTSA risk.

CONCLUSION

MetS was associated with an increase in the risk of LTSA due to various diseases among Japanese workers.

Visit-to-visit variability of blood pressure and cardiovascular events among the working-age population in Japan: findings from the Japan Epidemiology Collaboration on Occupational Health Study

Increased visit-to-visit variability (VVV) of blood pressure, which is calculated based on several readings, has been suggested to be a significant predictor of cardiovascular events and mortality, independent of mean blood pressure. This study examined associations between the VVV of systolic blood pressure (SBP) measured annually and cardiovascular disease (CVD) events among 72,617 Japanese subjects. Data were obtained from the Japan Epidemiology Collaboration on Occupational Health Study, which is an ongoing epidemiological survey of workers in Japan. VVV was calculated as the coefficient of variation of SBP readings from 2008 to 2011; information on fatal and nonfatal CVD events was collected from registries of specific outcomes between April 2012 and March 2019. A Cox proportional hazards model was applied to investigate associations after adjusting for mean SBP between 2008 and 2011 and covariates. During the 7-year follow-up period, there were 63 CVD fatalities and 314 CVD events (combining fatal and nonfatal events). The results showed that a one-standard deviation increase in VVV was associated with a significant increase in the risk of CVD mortality (hazard ratio [HR] = 1.42; 95% confidence interval [CI] = 1.32-1.54); those in the highest tertile had a 3.20 times (95% CI = 1.26-8.17) higher risk of CVD mortality than those in the lowest tertile. We found less pronounced associations regarding CVD events (HR = 1.08, 95% CI = 1.02-1.15). In conclusion, VVV was significantly associated with CVD mortality in our Japanese working population.

Trajectories of body mass index and waist circumference before the onset of diabetes among people with prediabetes

BACKGROUND & AIMS

To investigate trajectories of body mass index (BMI) and waist circumference (WC) among prediabetic people who progressed to diabetes, people who remained with prediabetes, and those who returned to normoglycemia.

METHODS

We used data from 22,945 prediabetic people who received an annual health checkup for up to eight years. The development of diabetes was defined using the American Diabetes Association criteria. People who did not progress to diabetes during the observation period were classified as 'remained with prediabetes' or 'returned to normoglycemia', based on their last health checkup data. Trajectories of BMI and WC were evaluated using linear mixed models for repeated measures, with adjustment for a wide range of covariates.

RESULTS

During the study period, 2972 people progressed to diabetes, 4706 returned to normoglycemia, and 15,267 remained with prediabetes. People who progressed to diabetes had a larger increase in mean BMI from 7 years to 1 year prior to diagnosis, which was about three times that of people who remained with prediabetes (annual change rate, 0.20 [95% confidence interval; 0.15 to 0.24] vs 0.06 [0.04 to 0.08] kg/m² per year, P < 0.001), regardless of their BMI levels at the initial health checkup. Among people who returned to normoglycemia, mean BMI remained almost the same over time (-0.04 [-0.09 to 0.002] kg/m² per year), except for those with obesity (-0.16 [-0.28 to -0.05] kg/m² per year). As for WC, the annual change rate among people who developed diabetes was about 7 times that of people who remained with prediabetes (0.38 [0.32 to 0.45] vs 0.05 [0.03 to 0.08] cm per year, P < 0.001). We also observed a constant mean WC over time among people who had no central obesity and later returned to normoglycemia (-0.02 [-0.06 to 0.03] cm per year), and an annual decrease in mean WC among those who had central obesity and later returned to normoglycemia (-0.40 [-0.47 to -0.32] cm per year).

CONCLUSIONS

Our study provides strong evidence that avoiding weight gain could help prediabetic people minimize the risk of developing diabetes, regardless of whether they are obese. Losing weight could help obese people restore normoglycemia from a prediabetic state, whereas maintaining current weight may help nonobese people return to normoglycemia.

High-intensity interval training improves metabolic syndrome and body composition in outpatient cardiac rehabilitation patients with myocardial infarction

BACKGROUND

To examine the effect of high-intensity interval training (HIIT) on metabolic syndrome (MetS) and body composition in cardiac rehabilitation (CR) patients with myocardial infarction (MI).

METHODS

We retrospectively screened 174 consecutive patients with MetS enrolled in CR following MI between 2015 and 2018. We included 56 patients who completed 36 CR sessions and pre-post dual-energy X-ray absorptiometry. Of these patients, 42 engaged in HIIT and 14 in moderate-intensity continuous training (MICT). HIIT included 4-8 intervals of high-intensity (30-60 s at RPE 15-17 [Borg 6-20]) and low-intensity (1-5 min at RPE < 14), and MICT included 20-45 min of exercise at RPE 12-14. MetS and body composition variables were compared between MICT and HIIT groups.

RESULTS

Compared to MICT, HIIT demonstrated greater reductions in MetS (relative risk = 0.5, 95% CI 0.33-0.75, P < .001), MetS z-score (- 3.6 ± 2.9 vs. - 0.8 ± 3.8, P < .001) and improved MetS components: waist circumference (- 3 ± 5 vs. 1 ± 5 cm, P = .01), fasting blood glucose (- 25.8 ± 34.8 vs. - 3.9 ± 25.8 mg/dl, P < .001), triglycerides (- 67.8 ± 86.7 vs. - 10.4 ± 105.3 mg/dl, P < .001), and diastolic blood pressure (- 7 ± 11 vs. 0 ± 13 mmHg, P = .001). HIIT group demonstrated greater reductions in body fat mass (- 2.1 ± 2.1 vs. 0 ± 2.2 kg, P = .002), with increased body lean mass (0.9 ± 1.9 vs. - 0.9 ± 3.2 kg, P = .01) than the MICT. After matching for exercise energy expenditure, HIIT-induced improvements persisted for MetS z-score (P < .001), MetS components (P < .05), body fat mass (P = .002), body fat (P = .01), and lean mass (P = .03).

CONCLUSIONS

Our data suggest that, compared to MICT, supervised HIIT results in greater improvements in MetS and body composition in MI patients with MetS undergoing CR.

Prediabetes and cardiovascular disease risk: A nested case-control study

BACKGROUND AND AIMS

We aimed to examine the risk of cardiovascular disease (CVD) with persistent prediabetes during the last four years prior to a CVD event in a large occupational cohort in Japan.

METHODS

We performed a nested case-control study using data from the Japan Epidemiology Collaboration on Occupational Health Study. A total of 197 registered cases of CVD were identified and matched individually with 985 controls according to age, sex, and worksite. Prediabetes was defined as fasting plasma glucose 100-125 mg/dL and/or HbA1c 5.7-6.4%. Persistent prediabetes was defined as having prediabetes at years one and four prior to the onset/index date; persistent normoglycemia was similarly defined. Associations between prediabetes and CVD risk were assessed using conditional logistic regression models.

RESULTS

Compared with people with persistent normoglycemia over the four years prior to the onset/index date, the unadjusted odds ratio (95% confidence interval) for CVD was 2.88 (1.56, 5.32) for people with persistent prediabetes. After adjusting for BMI, smoking, hypertension, and dyslipidemia assessed four years before the onset/index date, the association was slightly attenuated to an OR (95% confidence interval) of 2.62 (1.31, 5.25). Prediabetes assessed at single time points was also associated with an elevated risk of CVD, with multivariable-adjusted odds ratio (95% confidence interval) of 1.72 (1.12, 2.64) and 2.13 (1.32, 3.43) for prediabetes at one and four years prior to the onset/index date, respectively.

CONCLUSIONS

Prediabetes is associated with an increased risk of CVD. Identification and management of prediabetes are important for the prevention of CVD.

Metabolic syndrome status over 2 years predicts incident chronic kidney disease in mid-life adults: a 10-year prospective cohort study

We investigated whether changes in MetS status over two years modify the 10-year risk of CKD and proteinuria. A prospective cohort study was conducted in 7,251 subjects without CKD at baseline. We categorized subjects according to MetS status over two years: non-MetS (no MetS at either visit), intermittent MetS (positive for MetS at one assessment), and persistent MetS (positive for MetS at two assessments). The hazard ratio (HR) of new-onset CKD over 10-year was calculated using Cox models. During the 10-year follow-up period, 923 (12.7%) developed CKD. Compared to the non-MetS group, the fully adjusted HR for new-onset CKD was the highest in the persistent MetS group (HR, 1.53; 95% CI, 1.23-1.90), followed by the intermittent MetS group (HR, 1.29; 95% CI, 1.04-1.59) (P for trend <0.001). The HR for developing proteinuria was 1.79 (95% CI, 1.15-2.79) in the persistent MetS group and 0.70 (95% CI, 0.42-1.19) in the intermittent MetS group when the non-MetS group was considered as the reference group. Temporal changes in MetS status over two years influenced the 10-year risk of incident CKD and proteinuria. Our findings suggest that monitoring and strictly controlling MetS are important in preventing renal function decline.