Effect of age, period and birth–cohort on the frequency of glucose-6-phosphate dehydrogenase deficiency in Sardinian adults

Abstract

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited disorder common in Sardinia. In this study, the frequency variation of G6PD-deficiency across age groups and birth cohorts was investigated using Age–Period–Cohort analysis.Methods: Data were collected from the clinical records of 11,252 patients (6975 women, age range 17–94 years) who underwent endoscopy between 2000 and 2016 at a teaching hospital (University of Sassari), Italy. G6PD status was assessed by enzymatic assay based on G6PD/6GPD ratio. A Poisson log-linear regression model was used to identify age and time trend in G6PD deficiency.Results: Enzyme deficiency was detected in 11.4% of the entire cohort (men: 7.9%; women: 13.6%). Age–Period–Cohort analysis showed no inflection points across age groups, especially after age 80. The effects of time period and birth cohorts on G6PD deficiency were negligible (frequencies before and after 1950 were 11.0% and 11.8%, respectively).Conclusions: These findings indicate that the frequency of G6PD deficiency does not vary significantly in oldest subjects. The lack of evidence for selection across the malaria eradication time may be explained by other factors, including somatic cell selection or misclassification of heterozygotes women as G6PD normal in the older birth cohorts. Additional molecular studies may help clarify these issues.Key messageThe frequency of glucose-6-phosphate dehydrogenase deficiency is stable across age groups and does not vary in generations born before or after malaria eradication.