Chronic obstructive pulmonary disease severity and its association with serum magnesium levels among patients at Moi Teaching and Referral Hospital, Eldoret

Abstract

Background: Chronic Obstructive Pulmonary Disease (COPD) is a progressive respiratory condition characterized by persistent airflow limitation and chronic symptoms such as dyspnea, cough, and sputum production. Magnesium plays a critical role in bronchodilation, neuromuscular function, and inflammatory modulation. Hypomagnesemia has been linked to increased COPD severity and exacerbation frequency. However, local data exploring this association remains limited. This study assessed the relationship between serum magnesium levels and COPD severity among patients at Moi Teaching and Referral Hospital (MTRH). Objectives: To determine COPD severity and its association with serum magnesium levels among COPD patients in MTRH. Methods: A hospital-based cross-sectional study was conducted at MTRH from January to June 2023, enrolling 102 COPD patients aged ≥40 years from outpatient and inpatient departments. Diagnosis was confirmed by spirometry (post-bronchodilator FEV₁/FVC <0.70), and patients were staged according to GOLD severity (I–IV). Serum magnesium was classified as hypomagnesemia (<0.7 mmol/L), normomagnesemia (0.7–1.05 mmol/L), or hypermagnesemia (>1.05 mmol/L). Data were analyzed using STATA v16. Categorical variables were reported as frequencies and percentages; continuous variables as means ± SD. Associations were tested using Chi-square and logistic regression, with adjusted odds ratios (aOR) and 95% confidence intervals. Ethical approval was obtained from the Moi Teaching and Referral Hospital/Moi University Institutional Research and Ethics Committee (MTRH/MU-IREC). Results: The mean age of participants was 71.3 ± 14.8 years, with females comprising 60.8% of the study population. Biomass exposure was nearly universal (99%), while 43.1% had a history of cigarette smoking. The overall mean serum magnesium level was 0.77 ± 0.12 mmol/L (range: 0.47-1.14 mmol/L). Patients with mild to moderate COPD (GOLD stages I-II) had a higher mean magnesium level (0.82 ± 0.09 mmol/L) compared to those with severe to very severe COPD (GOLD stages III-IV), who had a mean level of 0.74 ± 0.12 mmol/L. Hypomagnesemia (<0.7 mmol/L) was identified in 31 patients (30.4%), with 93.5% of them classified as having GOLD stage III or IV disease. There was a statistically significant association between hypomagnesemia and increased COPD severity (p = 0.001). Multivariate logistic regression analysis revealed that patients with hypomagnesemia had significantly higher odds of severe COPD (adjusted odds ratio [aOR] = 27.3; 95% CI: 4.38-170.19). Hypermagnesemia (≥1.05 mmol/L) was observed in only two patients (1.96%): one with GOLD stage II and another with GOLD stage IV, limiting meaningful interpretation. All participants were referred for routine clinical follow-up, with treatment plans tailored to the severity of their COPD. Conclusions: Hypomagnesemia was strongly associated with advanced COPD stages, suggesting it may serve as a potential marker of disease severity and a possible target for further clinical attention. Recommendations: Routine screening of serum magnesium levels may be considered in the evaluation of COPD patients, particularly those with more severe disease. Further research, including randomized controlled trials, is warranted to determine whether correction of hypomagnesemia can lead to improved clinical outcomes.