Prevalence of Self-Reported Swallowing Difficulties and Swallowing-Related Quality of Life Among Community-Dwelling Older Adults in India

Swallowing difficulties in older adults (individuals aged >60 years) has been recognized as an ‘geriatric syndrome’ affecting 40 million individuals in Europe [1]. Aging is an independent predictor of swallowing difficulties and has 20% higher risk in the population above of 65 years old [2]. Swallowing difficulties and aging may lead to health issues like aspiration pneumonia, reduced nutrition, and dehydration [3‐5], resulting in extended hospital stays and economic burden [6]. Thus, early identification and intervention for swallowing difficulties in older adults are crucial for promoting active aging. Video-fluoroscopy study of swallowing quantifies physiological variations observed in oral and pharyngeal regions among older adults [7]. It provides valuable insights for Speech-Language Pathologists in clinical decision-making. However, it does not provide insight into patients’ day-to-day challenges related to swallowing difficulties. Further, video-fluoroscopy studies are confined to objective data and do not assess the broader impact of swallowing difficulties on individuals’ health and their quality of life (QOL). In response to these limitations, self-reported measures have become an essential tool in the dysphagia practice.

The primary focus of self-reported measures are to gather reliable information directly from patients to help in shared treatment decisions [8], and to understand the psychosocial burden associated with health ailments [9]. Speech-Language Pathologists have used different self-reporting questionnaires such as the Eating Assessment Tool (EAT-10) [10‐17], Dysphagia Handicap Index (DHI) [18], Sydney Swallow Questionnaire [19], a combination of EAT-10 and Sydney Swallow Questionnaire [20] and M.D. Anderson Dysphagia Inventory [21] to identify individuals at risk for swallowing difficulties [22]. These questionnaires are popular for brevity and highly valued among clinicians due to their cultural adaption in different languages [23, 24]. The risk of swallowing difficulties in older adults have also been extensively studied using these self-reported measures [25], adding to our understanding of this neglected health issue [26].

The global estimate of swallowing difficulties among adults is reported as 43.8%, and this estimate increases to 48.1% in older adults [27]. Studies conducted over the years suggest that self-reported swallowing difficulties among community-dwelling older adults ranges from 9.8% to 53.8% [10, 12, 13, 15, 16, 28‐31]. According to a systematic review and meta-analysis of the literature, the prevalence of swallowing difficulties in community-dwelling older adults falls within the range of 5–72% [32]. Prevalence rates of self-reported swallowing difficulties in older adults vary depending upon: (1) settings—these rates range from 31.9% [33] to 77% [34] in hospitals, and from 14.9% [35] to 68% [36] in nursing facilities; (2) questionnaire used—23.7% of individuals reported difficulties when using the EAT-10 questionnaire, while only 9.49% reported issues on the Sydney Swallow Questionnaire [20], and (3) country-specific—the prevalence rates are 2.6% in United States [25], 10.6% in Canada [2], 22.1% in New Zealand [14], 25.1% in Japan [13].

Despite the wealth of studies across different domains and regions, there is currently no available data on self-reported swallowing difficulties for older adults within Indian population. Limited information suggests that 2% of older adults in India require full or partial assistance for feeding [37]. To the best of our knowledge, there is no shortage on availability or accessibility of self-reporting swallowing questionnaires in regional languages of India for research purposes or measuring clinical outcomes [38‐42]. However, for reasons not known to us, no previous attempts have been made to estimate the prevalence of self-reported swallowing difficulties among community-dwelling older adults in India. Considering the estimated 41% increase in the number of older adults in India in 2021, reaching 138 million [43], there is an urgent need to assess prevalence of self-reported swallowing difficulties among community-dwelling older adults aged >60 years in India. The findings of this study contribute valuable information for healthcare practitioners, aiding them in better understanding the scope of this issue within community-dwelling older adults in India. This can also prompt the integration of systematic screening protocols, such as the EAT-10 and/or DHI, into routine assessments to identify older adults with swallowing difficulties early.

The purpose of our study was to estimate the prevalence of self-reported swallowing difficulties and assess swallowing-related QOL in community-dwelling older adults of India. Additionally, we aimed to investigate whether swallowing-related QOL differed among older adults with and without self-reported swallowing difficulties.

The overall mean EAT-10 score was 3.34 ± 5.20. Females (3.83 ± 5.64) had higher scores compared to males (2.84 ± 4.68), and this sex difference was statistically significant [t(359) = 1.775, p = 0.017] at p < 0.05. Among older adults, 36.6% (n = 132) failed the EAT-10 (8.58 ± 5.47), indicating self-reported swallowing difficulties (Table 1). Independent t-test revealed a statistically significant difference between individuals with and without self-reported swallowing difficulties [t(359) = −22.566, p = 0.000] at p < 0.001. Among older adults with self-reported swallowing difficulties, 54.6% (n = 72) were females, and 45.4% (n = 60) were males. Further, 34.1% (n = 123) of older adults reported swallowing difficulties for the inquiry “Swallowing solids takes extra effort” followed by 32.7% (n = 118) for “I cough when I eat” and 29.9% (n = 108) for “When I swallow food sticks in my throat” (Table 2).

The mean total DHI was 7.56 ± 12.33, with females scoring higher (8.48 ± 13.70) than males (6.66 ± 10.77). However, the sex differences in total DHI were not statistically significant at p > 0.05. 47.4% (n = 171) of older adults scored 15.61 ± 14.05 in total DHI (Table 3), which is greater than the normative value ≥4, suggesting swallowing difficulties has a negative impact on their QOL. In older adults self-reporting poor swallowing-related QOL, 52.1% (n = 89) were females, and 47.9% (n = 82) were males. Older adults self-reported higher scores on the physical scale of the DHI than functional and emotional scales (Table 3). MANOVA test revealed a statistically significant difference between older adults with and without self-reported poor swallowing-related QOL for physical [F(1) = 473.712, p = 0.000], functional [F(1) = 132.748, p = 0.000], emotional [F(1) = 52.941, p = 0.000], and total DHI scores [F(1) = 224.733, p = 0.000] at p < 0.001. Pairwise comparison by Bonferroni post hoc test also revealed a statistically significant difference at p < 0.001 (Table 4). Further, 35.7% (n = 129) older adults reported swallowing difficulty for the query “I need to drink fluids to wash food down”, followed by 29.6% (n = 107) “I feel depressed because I can’t eat what I want” and for 29.1% (n = 105) “I avoid some foods because of my swallowing problem” (Table 5).

In the overall severity of swallowing difficulties, 29.1% (n = 105) older adults reported their overall difficulties ranging from mild to severe (Table 6). Total DHI scores increased as the overall severity of swallowing difficulties increased. In the subscales, the physical domain of DHI had higher scores compared to the functional and emotional domains in normal and mild overall severity of swallowing difficulties. However, in moderate severity, both physical and functional domains were equally affected, while functional scores were greater than physical domain in the severe category. MANOVA test revealed a statistically significant difference across normal to severe ratings for physical [F(3) = 157.771, p = 0.000], functional [F(3) = 112.850, p = 0.000], emotional [F(3) = 63.976, p = 0.000], and total DHI [F(3) = 149.271, p = 0.000] at p < 0.001. Bonferroni post hoc test also revealed a statistically significant difference at p < 0.05 (Table 7).

A comparison between EAT-10 and total DHI revealed that older adults who passed the EAT-10 (0.32 ± 0.66) had total DHI scores within normal limits (1.86 ± 3.31). However, older adults who failed the EAT-10 (8.58 ± 5.47) had total DHI scores greater than normative data (17.45 ± 15.59), suggesting that their swallowing difficulties had a negative impact on their QOL. A Karl Pearsons correlation coefficient value of r = 0.86 indicated a strong positive correlation between EAT-10 and total DHI scores at p = 0.000. When comparing age with EAT-10 and total DHI scores (Fig. 1), Karl Pearsons correlation coefficient values of 0.41 and 0.34 were obtained, suggesting moderate and weak positive correlation, respectively.

The present study estimated self-reported swallowing difficulties using the EAT-10 and assessed swallowing-related QOL using DHI questionnaire among community-dwelling older adults in India. The findings of this study add to existing literature, confirming that age significantly impacts swallowing, with a substantial proportion of older adults self-reporting swallowing difficulties [10‐16, 18‐20].

Table 8 presents the prevalence of self-reported swallowing difficulties among community dwelling-older adults from various countries, as estimated using EAT-10 questionnaire. As illustrated in Table 8, the prevalence rates range from 5.7% to 53.8% across different studies, encompassing a minimum of 443 community-dwelling older adults to maximum of 4403 participants. Additionally, the mean EAT-10 scores reported in these studies varied between 0.72 and 5.8. Notably, the results of our study are consistent with the literature, as we observed a comparable estimated prevalence of 36.6% within our cohort of 361 older adults.

Furthermore, among the seven studies listed in Table 6, six of them utilised a cut-off score of ≥3 on the EAT-10 questionnaire to identify individuals with self-reported swallowing difficulties. One study, however, adopted a cut-off score of ≥2 [15]. In their study, Kertscher et al. [15] reported a prevalence rate of self-reported swallowing difficulties of 9.8–21.9% for a cut-off ≥3. This estimate increased to 12.4–26.2% when the EAT-10 cut-off was reduced to ≥2. It is important to note that this variation in the cut-off score between ≥2 and ≥3 for the EAT-10 is widely discussed in the literature, a point emphasized in the works of Rofes et al. [45]. Their study reported that lowering the cut-off scores to 2 increases the sensitivity without affecting specificity rates, ultimately reducing the false negative rate. However, it is worth mentioning that a recent evidence synthesis study recommended a cut-off score of ≥3 for the EAT-10 questionnaire, as it offers better diagnostic accuracy in identifying individuals at risk for swallowing difficulties [24]. This recommendation guided our choice to follow the ≥3 cut-off score to distinguish community-dwelling older adults with self-reported swallowing difficulties from those without.

In contrast to the wealth of information available regarding the EAT-10 questionnaire, there is a paucity of information regarding the use of DHI to assess the status of swallowing-related QOL among older adults. This point is partly supported by the five studies included in the systematic review and metanalysis, which aimed to establish normative data for DHI [44]. Further, our literature search yielded only two studies that assessed swallowing-related QOL using DHI in older adult populations [18, 46]. In the study conducted by Mulheren et al. [18], it was found that 60% (n = 12) of the older adults self-reported a poor swallowing-related QOL, with a total DHI score averaging 7.25 ± 10.75. However, it is important to exercise caution when generalizing these findings, given the relatively small sample size of 32 older adults and the wide age range, spanning from 62 to 91 years. Another study by Hazelwood et al. [46] reported that older adults experienced a moderate impact on their swallowing-related QOL. It is worth noting that a direct comparison between our study and Hazelwood et al. [46] is not feasible, as their study also included younger and middle-aged adults, ranging from 25 years to older adults aged up to 95 years. Therefore, further research is warranted to assess swallowing-related QOL among community-dwelling older adults using the DHI questionnaire to draw conclusions.

Older adults in our study reported the highest swallowing difficulties for specific symptoms, including difficulty swallowing solids, cough while swallowing, and food sticking in throat, as indicated by their responses on the EAT-10 questionnaire. These findings align with previous literature that older adults frequently experience coughing and food sticks in throat [10, 12, 13, 15]. Interestingly, the reports of difficulty swallowing solids are a novel observation among older adults, not previously reported in prevalence studies that have utilized EAT-10 questionnaire. However, objective evaluations of swallowing, such as the Test of Mastication and Swallowing Solids, have reported a functional decline in swallowing solids with increase in age [47, 48]. Further investigation is warranted to explore the underlying mechanisms for addressing the emerging issue of difficulty swallowing solids in older adults, while also continuing to examine the broader spectrum of swallowing difficulties and their impact on aging populations.

In the total DHI domain, our results suggest that older adults scored the highest on the physical scale, indicating a significant impact on their physical well-being due to swallowing difficulties. These findings are consistent with the study conducted by Mulheren et al. [18], where older adults scored 4.63 ± 5.62 on the physical scale, 1.5 ± 3.45 on functional and 1.13 ± 2.78 on the emotional scale. Furthermore, when examining the top three highest reported swallowing difficulties in each scale, it becomes evident that these difficulties are spread equally (one question each) across the physical (drink liquids to wash food down), functional (avoid some food because of swallowing difficulties), and emotional (feel depressed for not able to eat what I want) scales. This highlights the comprehensive impact of swallowing difficulties on an older adult’s overall swallowing-related QOL, encompassing physical, emotional, and functional aspects.

In our study, the mean scores for participants failing the EAT-10 and DHI were relatively low. Upon closer examination of the data, it was observed that the difference in the range of swallowing difficulties was also minimal. This suggests that swallowing difficulties in older adults of the study may not be severe. This notion is further highlighted by the results indicating that the overall severity of swallowing difficulties was predominantly rated as ‘normal’ and ‘mild’. In addition, females gave higher self-ratings compared to males. These results support previous research indicating that older female adults are more likely to report higher levels of swallowing difficulties than males [2, 12, 25, 49]. Similar to age being an independent predictor of self-reported swallowing difficulties, female older adults are reported to be 20% more likely to self-report swallowing difficulties than age-matched males [2]. Furthermore, Dantas et al. [12] study reported that 11.7% of females self-reported swallowing difficulties with EAT-10 scores ranging 0–20, in contrast to 5.9% of males who had EAT-10 scores of 0–8 at p < 0.01. However, when swallowing was longitudinally monitored at two time points, a significant association was reported between total scores of the Sydney Swallow Questionnaire with age and sex in 2009, which changed to no significant association with age and sex in 2012 [19]. Differences in the results of age and sex cohorts between the study using EAT-10 [12] and Sydney Swallow Questionnaire [19] can be attributed to the differing designs of the two questionnaires [20]. Overall, these findings emphasize the need for healthcare professionals to consider sex-specific factors when evaluating and addressing swallowing difficulties in older adults. A more thorough approach that recognizes sex-related differences in symptoms and outcomes can enhance dysphagia screening.

This study is the first to use EAT-10 and DHI questionnaires to assess self-reported swallowing difficulties and swallowing-related QOL in community-dwelling older adults. We obtained a strong positive correlation between EAT-10 and DHI scores at p < 0.001. These findings are consistent with those of Hazelwood et al. [46], who also reported a strong positive correlation (r = 0.817) between EAT-10 and DHI scores. However, Hazelwood et al. [46] cautioned against using both the EAT-10 and DHI due to the potential redundancy in measurement tools. This observation raises an interesting point because the EAT-10 primarily serves as a screening tool for identifying swallowing difficulties, while the DHI is designed to assess swallow outcomes related to swallowing-related QOL. Further research and discussion are warranted to explore the potential overlap or complementarity of these two tools in assessing swallowing difficulties and their impact on the QOL among older adults. Nonetheless, we anticipate a shift in the trend of utilizing DHI from solely a patient-reported outcome questionnaire to a self-reporting tool for dysphagia symptoms, especially with the publication of normative data [44]. To our knowledge, this is the first study to use DHI to determine the prevalence of self-reported swallowing-related QOL among community-dwelling older adults.

In conclusion, our study reveals that 36.6% of community-dwelling older adults in India self-report swallowing difficulties, while 47.4% experience a diminished swallowing-related QOL. This information underscores the importance of Speech-Language Pathologists actively implementing more screening programs to identify older adults at risk of age-related swallowing difficulties. Furthermore, these findings can serve as a valuable resource for patient education. Policymakers can leverage the results of this study to inform policies and healthcare practices specific to India. In the future, studies should supplement self-reports with objective tests of swallowing to determine the presence or absence of swallowing difficulties in older adults. It is also essential to evaluate swallowing capacities of older adults residing in nursing homes and old age homes. Lastly, it would be of interest to compare the reports of swallowing difficulties provided by family members and/or caregivers with self-reports of older adults.