Spirometric restrictive ventilatory pattern and type 2 diabetes mellitus in a tertiary hospital in Cameroon: A comparative study

Background: The objective of this study was to assess the association between spirometric restrictive ventilatory pattern (sRVP) and type 2 diabetes mellitus (T2DM) and investigate factors associated with sRVP in subjects with T2DM.

Materials and methods: In this comparative cross-sectional study, subjects with T2DM (diabetes group) were compared to a group of subjects without diabetes (non-diabetes group) from December 2018 to March 2019 (4months) at the National Obesity Center of the Yaoundé Central Hospital. sRVP was defined as the ratio of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) above the lower limit of normal, and FVC<80% of predicted values. Logistic regression was used to identify factors associated with sRVP.

Results: Overall 277 subjects were included in each group. The prevalence [95% confidence interval (95% CI)] of sRVP in the diabetes and non-diabetes groups was 39.4 (33.6-45.1) % and 34.3 (28.9-40.1) %, P=0.218. After multivariate analysis, we did not find an independent association between s sRVP and T2DM [odds ratio (95% CI): 1.13 (0.79-1.63), P=0.418]. The only independent factor associated with sRVP in subjects with T2DM was the presence of chronic vascular complications [odds ratio (95% CI): 1.99 (1.11-3.55), P=0.019].

Conclusion: One-third of patients with type 2 diabetes mellitus have sRVP. There is no independent association between sRVP and T2DM. The presence of chronic vascular complications is associated with sRVP in T2DM. Diagnosis of sRVP in subjects with T2DM presenting chronic vascular complications would help to provide a holistic management.