Polyclonal Hypergammaglobulinemia in a Randomized Sample of Ghanaian Adult Males.

Introduction Diffuse or polyclonal hypergammaglobulinemia has been associated with multiple medical conditions such as autoimmune diseases, infections, and chronic liver diseases. However, the possibility of differences in gamma globulin levels in different races and its association with environmental and socioeconomic factors is not well studied.

Method A randomized sample of 917 adult males (50–74 years) in an urban community in Ghana underwent in-person interview and health examination. Serum from all persons was analyzed by electrophoresis performed on agarose gel. Those found to have a monoclonal protein (n=54) were excluded from further analysis. Gamma globulin levels were measured in the remaining 863 samples. Associations between selected characteristics and gamma globulin levels were assessed by Chi-square test and logistic regression models.

Results The median gamma globulin level was 1.86 gm/dl. Seventy three percent of the study population had gamma globulin levels above the 1.6 gm/dl reference level and will be considered to have hypergammaglobulinemia. Surprisingly, 25% had gamma globulin levels above 2.17 gm/dl. In univariate analysis increased gamma globulin levels were associated with older age within the study population. Only 54% of the males aged 60 yrs or younger had gamma globulin levels above 1.6 gm/dl compared to 69% in those older than 60 yrs (p=0.007). Higher education level was associated with a low prevalence of hypergammaglobulinemia 51% compared with 74% in those with less than high school education (p <0.0001). Smoking was not associated (p=0.16) with gamma globulin levels. Although a higher proportion (71%) of people with history of alcohol use had hypergammaglobulinemia compared to the control (63%) this was not statistically significant (p=0.07). Self-reported history of genital warts, genital herpes and meningitis was associated with hypergammaglobulinemia, whereas syphilis, malaria, cholera, gonorrhea, hepatitis, measles and tuberculosis had no association with gamma globulin levels in univariate analysis.

Conclusion Three quarters of this randomized sample of Ghanaian adult males has hypergammaglobulinemia based on current laboratory definitions. More work is needed to uncover underlying causes for the observed high gamma globulin levels in this population. Further evaluation of a younger population with less environmental influence may help explain whether this is due to genetic differences, environmental exposures, or a combination.