OSTEOPENIA E FATORES ASSOCIADOS NA DOENÇA RENAL CRÔNICA NÃO DIALÍTICA

Abstract

Mineral and bone metabolism disorder (CKD-MBD) is a highly prevalent complication among individuals with chronic kidney disease. This disorder is defined by the presence of biochemical abnormalities, skeletal remodeling disorders, or extraskeletal calcification. This study aimed to determine the factors associated with osteopenia in individuals with non-dialytic chronic kidney disease. This was a longitudinal study conducted with 134 individuals undergoing non-dialytic treatment for CKD, monitored over a period of 12 months, at stages 3A, 3B, and 4, of both sexes, aged 18 years or older. Data collection was performed at two time points: T1 (inclusion) and T2 (after 12 months). Sociodemographic, lifestyle, anthropometric, clinical, laboratory, and imaging data were collected. Blood samples were drawn after a 12-hour fast to analyze creatinine, fasting glucose, sodium, calcium, parathyroid hormone (PTH), vitamin D, and phosphorus. Additionally, 24-hour urine samples were collected to measure sodium and magnesium. Anthropometric measurements included body mass and height. Body composition was assessed by Dual-energy X-ray Absorptiometry (DEXA). The geospatial distribution of osteopenia and air pollution in the city of São Luís was analyzed using geoprocessing techniques, considering the Health Districts as reference units. To evaluate the association between osteopenia and risk factors, a generalized linear mixed-effects model was applied. The Odds Ratio (OR) and their respective 95% Confidence Intervals (CI) were estimated to measure the magnitude of associations. The prevalence of osteopenia was higher among males (55.7%), individuals aged ≥60 years (61.4%), and those earning between one and three minimum wages (64.8%). A higher frequency of osteopenia was observed among individuals with a high school education (48.3%). Regarding lifestyle factors, 55.8% were smokers, 45.1% alcohol consumers, and 57.5% sedentary. Overweight was prevalent in 46.6% of the sample. Regarding clinical characteristics, osteopenia was more frequent in normotensive patients (82.9%) and those diagnosed with diabetes mellitus (56.8%). In the geospatial analysis, a greater number of osteopenia cases was concentrated in the urban area of São Luís. A higher percentage of osteopenia cases was recorded in areas outside the influence of air pollution. In the mixed-effects logistic regression model, parathyroid hormone (PTH) was associated with osteopenia (OR = 1.1; CI: 1.00–1.02; p-value = 0.035). However, urinary magnesium (Mg-U) was associated as a protective factor (OR = 0.1; CI: 0.98– 1.00; p-value = 0.026). In the group analysis over time, significant differences were observed in systolic blood pressure (SBP) (p-value = 0.033), urinary magnesium (p-value = 0.035), and estimated glomerular filtration rate (eGFR) (p-value = 0.047). The results of this study indicated that male sex, age ≥60 years, overweight, alcohol consumption, smoking, and a sedentary lifestyle were associated with a higher prevalence of osteopenia. Moreover, a greater concentration of osteopenia cases was found in urban areas and outside the influence of air pollution. Serum PTH levels were identified as a risk factor for osteopenia, while 24-hour urinary magnesium levels were a protective factor. Throughout the study period, a trend toward increasing SBP and decreasing 24-hour urinary magnesium and eGFR levels was observed.