Chronic Kidney Disease Linked to Tooth Loss in Postmenopausal Women

Findings from a recent study suggest chronic kidney disease (CKD) is significantly associated with tooth loss in postmenopausal women, highlighting the importance of considering oral and bone health in this patient population.¹

Results from the analysis of the Korean National Health and Nutrition Examination Survey (KNHANES) 2010-2018 data showed estimated glomerular filtration rate (eGFR) was linked to having ≥ 20 adult teeth, with postmenopausal women with CKD having greater tooth loss compared to those without CKD.¹

"This study highlights the known link between chronic kidney disease and bone metabolism. Increased attention to oral and bone health is warranted in postmenopausal women with chronic kidney disease, in addition to meticulous efforts aimed at preserving kidney function. Conversely, oral health is a window to overall health, and good oral hygiene is important for women of all ages," Stephanie Faubion, MD, MBA, chair of the department of medicine at Mayo Clinic in Jacksonville and medical director for The Menopause Society, said in a press release.²

Reproductive hormones play a crucial role in the management of bone health but are subject to fluctuations during menopause. After menopause, women face a greater risk of certain medical conditions, including osteoporosis and cardiovascular disease. Similarly, eGFR rates generally decrease following menopause, associated with the development of CKD and changes in reproductive hormone levels potentially impacting bone health. Although previous studies have identified an association between kidney function and tooth count, this relationship has not been explored in the context of postmenopause.^1,3

To evaluate the association between CKD and tooth loss in postmenopausal women, investigators collected data from the KHANES 2010-2018. Conducted by the Ministry of Health and Welfare and the Korea Centers for Disease Control and Prevention, the KHANES consists of a health survey, a medical examination survey, and a nutrition survey.¹

The present study included 64,971 KHANES participants with oral examination information available. After excluding males, those < 40 and ≥ 80 years of age, and those with missing data, the final analysis included 8887 participants.¹

Menstruation status was self-reported, with positive response to “natural menopause” or “artificial menopause” considered postmenopausal. Tooth loss was defined as the number of permanent teeth lost from a total of 28 permanent teeth, excluding the third molars. For the purpose of analysis, investigators divided participants into 2 groups: PT20, defined as having ≥ 20 teeth present and tooth loss ≤ 8, and non-PT20, defined as having < 20 teeth present and tooth loss > 8. CKD was defined as an eGFR < 60 mL/min/1.73 m2 after calculating serum creatinine levels using the CKD-EPI 2021 creatinine equation.¹

In total, 6802 participants had PT20. Investigators pointed out non-PT20 participants were older and had significantly lower education and income levels (P <.05), also observing lower rates of annual oral examination, toothbrushing frequency, and oral product use among these participants (P <.05). Additionally, the proportion of participants with hypertension, diabetes, and CKD was significantly greater among non-PT20 (P <.05).¹

A total of 271 patients had CKD, including 6.3% (n = 126) of patients in the non-PT20 group and 2.0% (n = 145) of those in the PT20 group. Investigators noted the prevalence of CKD was approximately 3 times higher in the non-PT20 group than in the PT20 group, additionally pointing out the average number of teeth lost was greater in participants with CKD, especially in the 66 - 79 age group.¹

Upon analysis, the odds ratio (OR) of PT20 in participants with CKD was significant (OR, 3.28; 95% confidence interval [CI], 2.48‐4.34), as was the OR of PT20 for every 10 mL/min/ 1.73 m2 increase in eGFR (OR, 0.72; 95% CI, 0.69-0.75). After adjusting for covariates, CKD and eGFR were significantly associated with having ≥ 20 teeth (CKD OR, 1.41; 95% CI, 1.04-1.90; eGFR OR, 0.90; 95% CI, 0.86-0.94). Further analysis stratified by age group revealed the association between CKD and PT20 was significant in the 66 - 79 age group (OR, 1.45; 95% CI, 1.05-2.01) but not in the 40 - 65 age group.¹

Investigators called attention to several potential limitations to these findings, including the potential for self-reporting bias; the cross-sectional study design; and the lack of data for fluoride exposure.¹

“Menopause is recognized as a significant event in a woman's life, during which she may be exposed to various diseases and complications, necessitating careful attention to her healthcare needs,” investigators wrote.¹ “However, to our knowledge, no study has evaluated the association between CKD and tooth loss in postmenopausal women across the ages.”

References:

1. ^{Kim NY, Kim JE, Choi CH, et al. Chronic kidney disease in postmenopausal women is associated with tooth loss. Menopause. doi:10.1097/GME.0000000000002375}
2. ^{The Menopause Society. New Study Suggests Kidney Function Is Associated With Tooth Loss in Postmenopausal Women. June 12, 2024. Accessed June 12, 2024.}
3. ^{Mayo Clinic. Menopause. Diseases & Conditions. May 25, 2023. Accessed June 11, 2024. https://www.mayoclinic.org/diseases-conditions/menopause/symptoms-causes/syc-20353397}