Discussion

This study aimed to assess the prevalence and associated factors of periodontal disease among diabetic patients attending an outpatient diabetic clinic at MRRH. From this study's findings, it was found that the prevalence of periodontal disease was very high among diabetic patients. This finding is consistent with previous studies that have reported a high prevalence ranging 80-90% [9,13]. Most studies have attributed this high prevalence to the bidirectional relationship that exists between periodontal disease and diabetes. Chronic hyperglycemia promotes the formation and accumulation of advanced glycation end products (AGEs), which bind to their receptors (RAGE) on immune and endothelial cells, stimulating the release of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) [14]. This persistent inflammatory response impairs neutrophil function, disrupts collagen metabolism, delays wound healing, and enhances alveolar bone resorption, thereby increasing susceptibility to periodontal tissue destruction [15]. In turn, periodontal inflammation contributes to systemic inflammation, which increases insulin resistance and compromises glycemic control, reinforcing the bidirectional relationship between the two conditions [6,16,17]. Notably, in our study, 21% of the participants had uncontrolled blood sugar. A similar study conducted in Uganda reported a high prevalence of periodontal disease above 85% with a HbA1c mean score of 8.8 mmol/L, an indicator of the existence of this bidirectional relationship between periodontal diseases and poor glycemic control among study participants [9].

This study found that females are less likely to develop periodontal disease than their male counterparts. These results are consistent with other literature that highlights men as being at a higher risk of periodontal disease as compared to females [9,18,19]. As compared to males, females tend to exhibit better oral hygiene practices and are more proactive in visiting dentists [20]. Moreover, females with poor oral hygiene practices are still less prone to developing periodontal disease than their male counterparts [9]. Notably, females are less exposed to other risk factors of periodontal disease than men. For example, females are less likely to be current or former smokers than males, thus less likely to develop periodontal disease [9,21,22]. This necessitates gender-tailored interventions educating males about proper oral hygiene practices and proper health-seeking behaviors.

In this study, having a tertiary education was protective against periodontal disease, which concurs with other literature that associates low levels of education with a higher prevalence of periodontal disease [23]. This is also in line with a study that was conducted at a referral hospital in Uganda that found an association between lower levels of education and periodontal disease [9]. Educational level is a social determinant of health and a measure of one's economic status, and its effect on general well-being has been well documented [24]. Individuals with a higher level of education are more likely to be richer and therefore able to afford periodontal treatments, which are, in most cases, expensive, reducing their likelihood of suffering from the disease [9]. Additionally, higher education promotes health literacy, thus better health practices such as proper oral hygiene and social habits, which are essential in lowering periodontal disease risks [25,26]. Health educating masses in the lower socio-economic class about better health practices could bridge the literacy gap and, in turn, reduce the incidence of periodontal disease.

Surprisingly, alcohol consumption was slightly associated with lower odds of periodontal disease (AOR: 0.139, 95%CI: 0.042-0.466). This finding contradicts the majority of published literature, which reports a positive association between alcohol intake and periodontitis [27,28]. Individuals with high alcohol intake show changes in subgingival microbial composition and higher proportions of pathogens responsible for periodontal disease [29]. However, another study about alcohol and periodontal pockets showed no association between the two [30]. Another cohort study in Japan showed no association between alcohol consumption and the incidence of periodontal disease [28]. The very small number of participants who reported alcohol consumption (n = 26) and the lack of data on frequency, quantity, and type of alcoholic beverage limit the interpretation of this finding in this study. It is possible that individuals with advanced periodontal disease reduced or stopped alcohol intake due to oral pain or medical advice (reverse causation), or that residual confounding by unmeasured socioeconomic or behavioral factors exists. Focused studies exploring these drinking habits in the study population could possibly clarify the observed relationship in this study.

This study is one of the few studies in Uganda that systematically examined periodontal status using the WHO CPI. It was performed by qualified dental surgeons rather than relying on self-report data from participants. The consecutive recruitment of 336 diabetic patients from a large regional referral hospital's diabetic clinic enhances the representativeness of diabetic patients seeking care in rural southwestern Uganda.

However, some limitations should be acknowledged. This was a clinic-based study that employed consecutive sampling with a fairly tight inclusion criterion. These factors could have introduced selection bias, affecting the representativeness of the study sample and the generalizability of the study findings. The very high prevalence of periodontal disease (92.3%) may have reduced the power to detect weaker associations. Also, alcohol consumption was recorded only as a binary variable without details on quantity, frequency, or type, limiting the interpretation of the unexpected protective association observed. Notably, although we adjusted for several confounders, residual confounding by unmeasured factors like detailed oral hygiene practices, use of traditional oral hygiene tools, or genetic predisposition cannot be excluded. These considerations should be considered in future studies about this topic. Despite the limitations, this study still provides valuable insights into factors associated with periodontal disease among diabetic patients.