The associations between alcohol intake and cardiometabolic risk in African-origin adults spanning the epidemiologic transition

Background

Cardiometabolic (CM) risk affects approximately 25% of adults globally, and is diagnosed by meeting 3 out of 5 of the following CM risk factors: elevated blood pressure, high triglycerides, elevated blood sugar, low high-density lipoprotein (HDL) level, and abdominal obesity. Adults with CM risk are approximately 22% more likely to have higher mortality rates, and alcohol consumption may be associated with higher CM risk. While previous studies have investigated this potential connection, the majority of them did not include African-origin adults. Therefore, the study aimed to explore the association between alcohol intake and CM risk in 5 African-origin cohorts, spanning the epidemiologic transition in Ghana, South Africa, Jamaica, Seychelles and the United States of America.

Methods

Measurements included clinical measures for CM risk and self-reported alcohol consumption. Each participant was categorized into one of three drinking categories: non-drinker, light drinker (1–3 drinks daily for men and 1–2 drinks daily for women) and heavy drinker (4 or more drinks every day for men and 3 or more drinks per day for women). Using non-drinker status as the reference, the association between alcohol consumption status and prevalence of each of the five CM risk factors and overall elevated CM risk (having 3 out of 5 risk factors) was explored, adjusting for site, age and sex. Associations were explored using logistic regression and significance was determined using odds ratios (OR) and 95% confidence intervals.

Results

Neither light nor heavy drinking was associated with increased odds for having higher CM risk compared to nondrinkers (OR = 1.05, p = 0.792 and OR = 1.11, p = 0.489, respectively). However, light drinking was associated with lower odds for having low high density lipoproteins (HDL) cholesterol (OR = 0.69, p = 0.002) and increased risk for high triglycerides (OR = 1.48, p = 0.030). Heavy drinking was associated with elevated blood pressure (OR = 1.59, p = 0.002), high triglycerides (OR = 1.73, p = 0.006) and decreased risk of low HDL-cholesterol (OR = 0.621, p < 0.0005). Finally, country-specific analyses indicated that the relationship between heavy drinking and elevated CM risk varied widely across sites.

Conclusion

While several CM risk factors were associated with alcohol consumption, the associations were inconsistent and varied widely across five international cohorts of African-origin. Future studies should focus on understanding the individual site-related effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12128-2.

Metabolic characteristics of Africans with normal glucose tolerance and elevated 1-hour glucose: insight from the Africans in America study

INTRODUCTION

Risk of insulin resistance, dyslipidemia, diabetes and cardiac death is increased in Asians and Europeans with normal glucose tolerance (NGT) and 1-hour glucose ≥8.6 mmol/L. As African descent populations often have insulin resistance but a normal lipid profile, the implications for Africans with NGT and glucose ≥8.6 mmol/L (NGT-1-hour-high) are unknown.

OBJECTIVE

We performed oral glucose tolerance tests (OGTTs) in 434 African born-blacks living in Washington, DC (male: 66%, age 38±10 years (mean±SD)) and determined in the NGT group if either glucometabolic or lipid profiles varied according to a 1-hour-glucose threshold of 8.6 mmol/L.

METHODS

Glucose tolerance category was defined by OGTT criteria. NGT was subdivided into NGT-1-hour-high (glucose ≥8.6 mmol/L) and NGT-1-hour-normal (glucose <8.6 mmol/L). Second OGTT were performed in 27% (119/434) of participants 10±7 days after the first. Matsuda Index and Oral Disposition Index measured insulin resistance and beta-cell function, respectively. Lipid profiles were obtained. Comparisons were by one-way analysis of variance with Bonferonni corrections for multiple comparisons. Duplicate tests were assessed by к-statistic.

RESULTS

One-hour-glucose ≥8.6 mmol/L occurred in 17% (47/272) with NGT, 72% (97/134) with pre-diabetes and in 96% (27/28) with diabetes. Both insulin resistance and beta-cell function were worse in NGT-1-hour-high than in NGT-1-hour-normal. Dyslipidemia occurred in both the diabetes and pre-diabetes groups but not in either NGT group. One-hour glucose concentration ≥8.6 mmol/L showed substantial agreement for the two OGTTs (к=0.628).

CONCLUSIONS

Although dyslipidemia did not occur in either NGT group, insulin resistance and beta-cell compromise were worse in NGT-1 hour-high. Subdividing the NGT group at a 1-hour glucose threshold of 8.6 mmol/L may stratify risk for diabetes in Africans.