Respiratory symptoms and lung function among inmates in a Nigerian prison: a cross sectional study

Prisoners in low- and middle-income countries are vulnerable to poor lung health from multiple adverse conditions confronted within the prison such as overcrowding, poor ventilation and exposure to second hand smoke. Evidence for poor lung health in this disadvantaged group is needed to inform policy on prison conditions in this region. We assessed the respiratory symptoms and lung function measured by spirometry among prisoners in Enugu, Nigeria and explored the associations between them.

This was a cross‑sectional study among prison inmates aged 16-76 years. We assessed frequency of respiratory symptoms in the preceding one-year, previous respiratory diagnosis, tobacco smoking status and spirometry. The relationships between respiratory symptoms, smoking status and spirometry pattern were determined using the Chi‑square test.

Of 245 participants, 170 (69.4%) reported at least one respiratory symptom. In all, 214 (87.3%) performed spirometry and 173 (80.8%) had good quality spirometry tests. Using the Global Lung Function Initiative (GLI) predicted values for 'African Americans', spirometry results were abnormal in 41 (23.7%) of the participants and when the GLI reference values for 'Other' ethnic groups was applied, 78 (45.1%) had abnormal results. Restrictive impairment was most common occurring in 21 (12.1%) and 59 (34.1%) respectively based on the two reference values, and obstructive pattern was found in 18 (10.4%) and 13 (7.5%) respectively. There was no significant association between abnormal spirometry pattern and presence of respiratory symptoms or smoking status. No previous diagnosis for asthma, or bronchitis/chronic obstructive pulmonary disease (COPD) had been made in any of the participants.

We reported high rates of respiratory symptoms and abnormal lung function with under-diagnosis of chronic respiratory diseases among inmates in Enugu prison. The restrictive abnormalities based on GLI equations remain unexplained. There is need for improvement in prison facilities that promote lung health and enhanced access to diagnosis and treatment of respiratory non-communicable disease.