Health Literacy and Time-Specific Toothbrushing Practices in Older Adults: An Analysis of the Korean National Health and Nutrition Examination Survey, KNHANES IX (2023).

BACKGROUND

Evidence remains limited on whether health literacy is associated with time-specific toothbrushing occasions across the day.

OBJECTIVE

To examine time-specific toothbrushing patterns according to health literacy levels and to determine whether lower health literacy was associated with failure to brush at key times among older adults in Korea.

METHODS

Using the KNHANES IX (2023), we analysed 1,836 adults aged ≥ 65 years. Toothbrushing on the previous day was reported for eight occasions (before breakfast, after breakfast, before lunch, after lunch, before dinner, after dinner, after having a snack, and before bedtime). Health literacy (10-item scale; 10-40) was categorised as low (≤ 28), moderate (29-30), or high (≥ 31). Complex-sample weighted logistic regression estimated ORs (95% CIs) for failure to brush at specific times with hierarchical adjustment (demographic characteristics, socioeconomic status, health practices).

RESULTS

Lower health literacy was more common among older adults and those with lower income/education. Brushing was most frequent after breakfast and after dinner. Compared with high health literacy, low health literacy was associated with higher odds of not brushing before breakfast (OR 1.43, 95% CI 1.02-2.00) and after lunch (OR 1.38, 95% CI 1.00-1.91) after adjustment for sociodemographic factors; associations were attenuated after full adjustment. No consistent associations were found for failure to brush after breakfast or before bedtime.

CONCLUSIONS

Health literacy was associated with time-specific toothbrushing, with before-breakfast and after-lunch brushing identified as priority prevention targets among older adults.