Effect of a Mobile-Based Hydration Tracking Program on Knowledge, Attitudes, and Behaviors in Older Adults

1.1 Definition and Importance of the Problem Maintaining adequate fluid intake is a critical component of health across all stages of life. Proper hydration is essential for regulating blood pressure, enabling biochemical reactions, supporting nutrient digestion and absorption, maintaining cell and tissue function, thermoregulation, joint lubrication, and the elimination of toxins from the body (Armstrong \& Johnson, 2018; Lorenzo et al., 2019; Li et al., 2023).

In older adults, various physiological and behavioral changes make it difficult to maintain adequate hydration. These include a diminished sense of thirst, reduced total body water, forgetfulness, aversion to the taste of water, fear of incontinence, and difficulty accessing fluids due to mobility issues. Such factors often lead to insufficient hydration and, eventually, to dehydration (Masot et al., 2020; Mentes \& Gaspar, 2020; Dmitrieva et al., 2024).

Dehydration is a common condition among the older adults, particularly in institutional settings, and is associated with numerous negative health outcomes. These include headaches, dizziness, urinary tract infections, constipation, medication toxicity, respiratory infections, reduced muscle strength, delayed wound healing, fatigue, increased risk of falls, and cognitive impairment (Paulis et al., 2022; Parkinson et al., 2023; Purvis \& Gion, 2024). In addition to increasing morbidity and mortality, dehydration extends hospital stays and increases readmission rates (Edmonds et al., 2021; Beck et al., 2021).

In Türkiye, studies indicate that approximately one in three individuals over the age of 65 attending outpatient clinics show signs of dehydration. Factors such as female gender, low education level, diabetes mellitus, and chronic kidney disease have been found to be associated with higher dehydration risk. Dehydrated individuals are also more likely to experience reduced physical functioning, sarcopenia, and falls (Atcıyurt et al., 2023).

While dehydration is often preventable, older adults may face challenges in recognizing or responding to their hydration needs. However, consistent daily fluid intake and regular monitoring can significantly reduce the risk. Hence, effective hydration self-management strategies are crucial for maintaining health and preventing complications among older adults (Jimoh et al., 2015; Garcia, 2022; Syed et al., 2024).

Recent interventions based on self-monitoring and digital support, such as wearable devices and mobile apps, have shown promising results. While there are some Turkish studies evaluating the effectiveness of education and auditory reminders (e.g., smartwatches) in nursing home residents (Çetin \& Eşer, 2022), there is a lack of randomized trials focused on mobile health apps specifically tailored for older adult users in Türkiye.

Mobile health (mHealth) applications can support older adults by helping them monitor their fluid intake independently and consistently. Compared to smartwatches, mobile apps offer broader interactivity, greater visual clarity, and more accessible learning tools including videos, infographics, and personalized feedback (Siette et al., 2020). Apps also provide reminders and motivational tools that can promote sustained behavioral change.

In this context, the mobile-compatible, web-based hydration tracking application "SIVI" was developed to help older adults monitor their fluid intake, learn about hydration, and receive personalized feedback. Designed using principles of gerotechnology and age-friendly usability, SIVI features large fonts, high-contrast colors, customizable daily fluid targets, visual feedback tools, educational videos, and a question-and-answer interface with the researcher.

SIVI's usability and design were informed by prior literature, expert input, and pilot testing with older adults. The program aims to empower older adults to take a more active role in managing their hydration, thereby improving health outcomes and quality of life.

1.2 Aim of the Study This study aims to examine the effect of a mobile-compatible, web-based hydration tracking program developed for older adults on their hydration knowledge, attitudes, behaviors, and daily fluid intake.

1.3 Research Question and Hypotheses Research Question: Does the use of the mobile-compatible, web-based hydration tracking application (SIVI) improve daily fluid intake and hydration-related knowledge, attitudes, and behaviors among older adults? Null Hypothesis (H0): There is no statistically significant difference between the intervention and control groups in hydration knowledge, attitude, behavior, and fluid intake scores after the intervention.

Alternative Hypotheses:

• H1: There will be a statistically significant increase in hydration knowledge scores in the intervention group compared to the control group.

• H2: There will be a statistically significant increase in hydration attitude scores in the intervention group compared to the control group.

* H3: There will be a statistically significant increase in hydration behavior scores in the intervention group compared to the control group. * H4: There will be a statistically significant increase in daily fluid intake in the intervention group compared to the control group.

2\. MATERIALS AND METHODS 2.1 Study Design This study is designed as a single-blind, block-randomized controlled trial. The aim is to assess the impact of the SIVI mobile-compatible web-based hydration tracking program on hydration knowledge, attitudes, behaviors, and fluid intake among community-dwelling older adults. The study will be conducted between October 2025 and March 2026 at Mehmet Fevzi Özsaruhan No. 24 Family Health Center in İzmir, Türkiye. Participants will be randomly assigned to either the intervention or control group in equal numbers using block randomization. To prevent bias, the statistician conducting data analysis will be blinded to group allocation.

2.2 Population and Sampling The study population will include individuals aged 65 to 84 years who live in the community and meet the inclusion criteria. A power analysis indicated that a sample of 26 individuals per group (total n=52) would provide 80% power to detect a moderate effect size. To account for potential dropouts, the sample size was increased to 35 participants per group (total n=70).

Inclusion Criteria:

• Aged 65 to 84 years

* Primary school education or higher * Cognitive, sensory, and motor abilities sufficient for mobile phone use * Willing to participate in the study * Owns a mobile phone compatible with the application * Daily fluid intake below ESPEN guidelines (≤2.0 L/day for men, ≤1.6 L/day for women)

Exclusion Criteria:

* Diagnosed with urinary incontinence * Neurological or psychiatric disorders affecting mental status * Severe hearing, vision, or speech impairments * Diagnosed illnesses affecting fluid intake (e.g., kidney failure, heart failure) * Swallowing difficulties * Limited ability to perform basic activities of daily living * Interruption in app use for one week or more * Health conditions that may affect hydration needs during follow-up 2.3 Data Collection Tools

The following validated and researcher-developed instruments will be used for data collection:

* Descriptive Characteristics Form * Fluid Intake Habits Form * Hydration Knowledge, Attitudes, and Behaviors Scale (HyKS): Adapted to Turkish through a rigorous translation-back translation process with expert review (Veilleux et al., 2020). * System Usability Scale (SUS): Administered to the intervention group only at the end of the study 2.4 Intervention: SIVI Application

The intervention group will receive face-to-face training and install the SIVI app, which they will use for eight weeks. Features of the app include:

* Personalized fluid intake targets * Daily reminders * Visual intake diary with cup/bottle icons * Progress tracking graphics * Educational videos and text modules * A secure Q\&A platform with the researcher * Feedback via digital badges when daily goals are met Participants in both groups will receive the same model of water bottle to facilitate standardized self-monitoring. Weekly follow-up calls and twice-daily SMS reminders will be used to reinforce app use in the intervention group. A family physician will monitor participants' health status throughout the intervention to ensure safety.

The control group will receive only routine care services. They will not use the app.

2.5 Data Collection Procedure

Data will be collected at three points:

• Baseline (Day 0): Informed consent, demographic data, HyKS, Fluid Intake Habits Form

* Midpoint (1 Month): Repeat HyKS and habits form, app usage data automatically extracted * Post-test (2 Months): Final data collection, including SUS for the intervention group Daily app usage is expected to take less than five minutes. 2.6 Data Analysis Statistical analysis will be performed using SPSS version 22.0. The Shapiro-Wilk test will assess normality. Depending on distribution characteristics, Student's t-tests or Mann-Whitney U tests will be used for between-group comparisons. Repeated measures ANOVA or Friedman tests will analyze within-group changes over time. Chi-square tests will be applied for categorical variables. Significance will be set at p\<0.05.

3\. ETHICAL CONSIDERATIONS AND LIMITATIONS 3.1 Ethical Considerations This study was approved by the Non-Interventional Research Ethics Committee. All procedures will be conducted in accordance with the Declaration of Helsinki and relevant national regulations. Written informed consent will be obtained from all participants prior to inclusion in the study.

Participation in the study is entirely voluntary, and participants are free to withdraw at any time without any consequences. Confidentiality and anonymity of the data will be strictly maintained. The application's backend will store data on encrypted servers compliant with Personal Data Protection Law.

The study does not involve any invasive procedures, and there are no known significant physical risks associated with participation. Participants can mute reminders or exit the app at any time.

A family physician on the research team will monitor participants for adverse events such as vomiting, fever, or upper respiratory tract infections. If any clinical condition arises that could affect hydration needs, the physician will advise whether the participant should pause app use.

3.2 Limitations Several limitations must be acknowledged in interpreting the study findings. First, the study is single-center and conducted only in İzmir, Türkiye, which may limit the generalizability of results to other regions or populations. Second, the sample is restricted to individuals who own smartphones and are digitally literate. Third, the follow-up period is limited to two months, and long-term effects of the intervention will not be evaluated.

Additionally, standardized bottles and visual diary features in the intervention group aim to minimize measurement variability. Lastly, outcome assessors and the data analyst will remain blinded to reduce risk of bias.

4\. CONTRIBUTIONS 4. Scientific and Practical Contributions

This study is expected to make several contributions to the field of geriatric health and mobile health (mHealth) interventions:

1. Innovation in Geriatric Care: This is the first randomized controlled trial in Türkiye to evaluate the effects of a mobile-compatible web-based hydration tracking program specifically developed for older adults. It offers a novel approach to behavioral change in hydration through digital self-management. 2. Contribution to Evidence-Based Practice: The findings of this study will contribute to the growing body of evidence supporting the use of mobile health technologies for promoting healthy behaviors in aging populations. If effective, the intervention may be integrated into routine primary care and geriatric servi

• System Usability Score of the Mobile Hydration Tracking Application [Срок оценки: Week 4 and Week 8 after intervention]