Associations between orthostatic hypotension and related factors in hospitalised older adults: a cross-sectional study in Turkey

Abstract

Background

Orthostatic hypotension is a prevalent condition in older adults. In light of its potential association with serious complications, the routine assessment of orthostatic blood pressure changes and the evaluation of factors associated with orthostatic hypotension in hospitalised older adults remain of current importance. Raising awareness among nurses, who are healthcare professionals closely involved in patient care, on this issue is essential.

Objective

To investigate the prevalence of orthostatic hypotension and its associated factors in hospitalised older adults.

Methods

This analytical cross-sectional study was conducted using a questionnaire and blood pressure measurements. Data were collected from 265 older adults hospitalised in the internal medicine clinics of a state hospital. Descriptive statistics and parametric and non-parametric tests were used for data analysis. Binary logistic regression analysis was performed for further evaluation. Orthostatic hypotension was assessed using the supine-to-standing test; when this was not feasible, the sit-to-stand test was used.

Results

Orthostatic hypotension was observed in 14.3% of the participants. Chronic kidney disease, regular medication use, and diuretic use appeared to be more common among participants with orthostatic hypotension. Participants who reported leg pain while standing were significantly associated with orthostatic hypotension (OR = 2.51; 95% CI: 1.24–5.05; p = 0.010). A statistically non-significant but increasing trend was observed in the association between regular medication use and orthostatic hypotension (OR = 3.21; 95% CI: 0.95–10.89; p = 0.061). A 1-mmHg increase in systolic blood pressure in the supine/sitting position was associated with orthostatic hypotension (OR = 1.08; p < 0.001), whereas higher systolic blood pressure measured at 3 min of standing was associated with a lower prevalence of orthostatic hypotension (OR = 0.91; p < 0.001).

Conclusion

Orthostatic hypotension was observed in approximately one out of every seven older adults. Older adults who report leg pain while standing at any time of day may be more likely to have orthostatic hypotension. Healthcare professionals should consider that orthostatic hypotension may still occur in individuals with higher systolic blood pressure in the supine position. Our findings may support the importance of assessing orthostatic hypotension using the supine-to-standing test, unless there is any factor that would prevent the test from being performed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-026-07435-5.

Introduction

Orthostatic hypotension (OH) is expressed as a health problem that is difficult to treat, chronic and negatively affects quality of life [15]. OH is defined as “a reduction of systolic blood pressure (SBP) of at least 20 mm Hg or diastolic blood pressure (DBP) of at least 10 mm Hg within 3 min of standing” [18]. OH may vary depending on age and associated comorbidities [52]. Because the risk of adverse health outcomes increases with aging, OH is a health problem that remains particularly important in older adults [59, 69]. In studies conducted in different countries, OH in older adults was reported in the range of 7.8% to 22.2% [45, 56, 58, 72]. The prevalence of OH in older adults in internal medicine wards can vary between 22 and 75% [65]. The prevalence of OH has been emphasised as 5% in individuals under 50 years of age and 30% in individuals over 70 years of age [52]. The direct proportional increase between age and OH makes it important to be aware of changes in the mechanism of OH development in older adults [8].

The mechanisms that may play a role in the development of OH with advancing age are known as (1) decrease in plasma volume, (2) inadequacy in blood pressure regulatory mechanisms, (3) changes in baroreceptor sensitivity and (4) changes in muscle tone [3, 39, 49, 70]. For all these reasons, OH is a potentially dangerous condition in older people [67].

In the literature, OH is associated with many factors that threaten the health of older adults such as coronary artery disease, myocardial infarction, stroke, falls, fractures, traffic accidents and mortality risk [8, 16, 20, 29, 40, 52]. Therefore, timely recognition and management of OH by health professionals may play an important role [8, 67]. In hospitalized patients, OH is often recognized after admission [68]. Nurses working with geriatric patients may play an important role in assessing symptoms related to OH that may lead to serious complications, identifying OH, and maximizing patient safety [22].

Background

The literature emphasizes the need to assess OH-related symptoms, falls, quality of life, side effects and blood pressure changes to determine a successful OH treatment [8]. In many countries, blood pressure measurements performed by nurses are relied upon to diagnose OH and accurate measurement and assessment of blood pressure is of critical importance [67]. Therefore, accurate assessment of OH and identification of factors associated with OH is an important nursing intervention in preventing potential complications.

When the literature is examined, there are studies on the frequency of OH and/or factors affecting OH in older adults. These studies have shown that OH has a high prevalence [48, 58], that it most commonly occurs within the first 1–2 min after standing [47], that it may be associated with multiple factors [72], and that frailty may be a risk factor for OH during the initial minutes after standing [58]. It has been pointed out that age-related muscle loss is accompanied by reduced hydration and less stable early morning postural SBP, which may be associated with an increased risk of OH and falls [4]. Frailty levels may be associated with OH [6, 33, 43]. Drug-induced OH is another common factor [5] and taking multiple drugs may lead to a higher risk [48, 50]. In particular, the observation of a decrease in the frequency of most drug-induced OH cases over time may indicate the clinical importance of early diagnosis and monitoring [51].

Blood pressure measurements are essential in the screening for OH. The literature recommends head-up tilt testing or the supine-to-standing test for the diagnosis of OH. Shaw et al. [60] emphasized that although these tests are considered the gold standard, they may not always be practical in routine clinical practice. In their study, Shaw et al. [60] used the standard diagnostic criteria for OH based on the supine-to-standing test as the gold standard to determine the optimal cutoff values for blood pressure reductions during the sit-to-stand test. They demonstrated that a SBP decrease of ≥ 15 mmHg or a DBP decrease of ≥ 7 mmHg optimally balanced the sensitivity and specificity of the sit-to-stand test. The same study also indicated that when the supine-to-standing test cannot be feasibly performed, the sit-to-stand assessment may serve as a simple screening tool. Based on these findings, we believe that maintaining the clinical relevance of OH assessment in older adults and ensuring that nurses—who are among the healthcare professionals most frequently involved in patient care and monitoring—conduct OH screening using appropriate methods and are aware of related factors is of great importance.

Purpose

We aimed to investigate the prevalence of orthostatic hypotension and its associated factors in hospitalised older adults. The research questions are as follows:

• What is the prevalence of OH among hospitalised older adults?

• Which factors are associated with OH among hospitalised older adults?

Methods

Design and participants

The study was analytical-cross-sectional and conducted within the limitations of nursing activities. The study was conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies [9].

The research was conducted in the internal medicine clinics (nephrology, neurology, internal medicine, chest and cardiology) of a public hospital between October 2023 and July 2024. According to the information obtained from the statistical unit of the hospital where the study was conducted, the number of older adults hospitalized in internal medicine clinics in the last year was 4804. In cases where the size of the population is known, the formula used to determine the sample size is stated as “n = [(N.t²)(p.q)/d²(N-1) + t².(p.q)]” (N: the number of the population, T: the value from the t-table at a certain confidence level (usually 95%) at infinite degrees of freedom (t-table value for 95% is 1.96), n: the optimum sample size to be determined, p: the frequency of occurrence of the examined event, q: (1-p) the probability of non-occurrence of the examined event, d: the possible standard deviation of the speed to be determined in the research (0.05)) [57].

The prevalence of OH in older adults was reported as 22.2% by Saedon et al. [56]. However, the literature indicates that this prevalence can reach up to 30% in older populations [14, 36, 52]). Therefore, for the purposes of sample size estimation and power calculation, a conservative mid-range prevalence of 25% was adopted to avoid underestimation of the required sample size and to ensure adequate statistical power. This approach is widely accepted in prevalence-based sample size calculations [37, 42]. Accordingly, the required sample size was calculated as 265 participants. During the research period, an average of 10 older adults per day and 304 older adults who met the inclusion criteria in total were reached on the days when the researcher visited the clinics. Since 39 of these individuals refused to participate in the study, the study was completed with 265 individuals.

Inclusion and exclusion criteria

The inclusion criteria for the study were as follows: individuals who were over 65 years of age, had no verbal or written communication barriers, were accompanied by a companion (a relative of the patient who gave verbal consent to support the older adult to change position) and volunteered to participate in the study.

The exclusion criteria were as follows: being bedridden; receiving chemotherapy for a hematological or oncological disease; receiving palliative care; having a diagnosis of dementia or Alzheimer’s disease; undergoing dialysis; having undergone hip or knee surgery; having a history of vertigo; having hemiplegia; the ability to stand only with the aid of a cane; or withdrawing consent at any stage of the study.

Data collection

Individuals over 65 years of age who were admitted to the internal medicine clinics for inpatient treatment were checked daily from the hospitalisation system (electronically). Data were collected by filling out a structured questionnaire form and measuring blood pressure by face-to-face interviews with older adults hospitalized in internal medicine clinics.

Data were collected at different times (in the morning between 09.30 and 11.00 or in the afternoon between 14:30 and 16:00) according to the availability of the researcher and the clinics where the data were collected. Postprandial hypotension assessment was performed 2 h after meals to reduce the influence of splanchnic circulation [26].

Measurements

Personal ınformation form

The form consisted of 13 items: two items assessing participants’ sociodemographic characteristics (age and gender) and items evaluating health-related factors, including the presence of chronic disease, medication use, symptoms associated with OH, as well as an orthostatic hypotension assessment table incorporating pulse rate and blood pressure measurements (Supplementary File) [18, 23].

The presence of OH-related symptoms was assessed by asking whether they felt these symptoms at any time during the day. For the evaluation of body mass index (BMI) in the form, the weight of the individual was first determined. The height value was recorded according to the participant's statement. BMI values below 18.5 kg/m2 were considered underweight, 18.5–24.9 kg/m2 normal weight, 25–29.9 kg/m2 overweight and ≥ 30 obese (Turkish Society of Endocrinology and Metabolism).

Evaluation of orthostatic hypotension

Classic OH occurs within 3 min of standing. The older adults in the study were assessed for classic OH. In this study, decreases in SBP or DBP were assessed by the ‘supine-to-standing’ test or ‘sit-to-stand’ test. In the literature, the ‘supine-to-standing’ test is stated as the ‘gold standard test’ for the diagnosis of OH [60]. OH was assessed using the " ‘supine-to-standing’ test in older adults who could transition from a lying to a standing position [18]. In older adults who could not transition from a lying to a standing position, OH was assessed using the "sit-to-stand test" [60]. Blood pressure of the participants was measured with a mercury sphygmomanometer.

The recommendations of national and international guidelines were taken into consideration in the provision of equipment, necessary infrastructure and environmental conditions for blood pressure measurement [41],Turkish Society of Cardiology National Hypertension Treatment and Follow-up Guidelines). Precautions were taken in case of syncope during blood pressure.

The supine-to-standing test steps were performed as follows:

• Participants rested in the supine position for 5 min at baseline.

• The first blood pressure measurement was assessed in the supine position just before the participant stood up.

• Blood pressure was re-measured at 1 min and 3 min after the individual stood up, and both measurements were completed for all participants evaluated using this test. A decrease of at least 20 mmHg in SBP or 10 mmHg in DBP occurring at either the 1-min or the 3-min measurement after standing was considered OH.

The sit-to-stand test was performed in the following steps:

• Participants were seated and rested for 5 min at baseline.

• The first blood pressure measurement was performed in the sitting position before the participant stood up.

• Blood pressure measurements were re-measured at 1 min and 3 min after the individual stood up, and were completed at both time points for all participants evaluated using this test. A SBP drop ≥ 15 mmHg or a DBP drop ≥ 7 mmHg at the 3-min measurement after changing from sitting to standing position was considered diagnostic of OH. The 3-min blood pressure reading was considered the primary measurement for the evaluation of OH; if a 3-min measurement could not be obtained, the 1-min measurement would have been taken into consideration. However, in the present study, blood pressure measurements at both the 1-min and 3-min time points were completed for all participants. Therefore, OH was considered based on the 3-min measurement results.

Data analysis

IBM SPSS v22.0 was used for all data analysis. The analyses were performed by a statistician. Kolmogorov–Smirnov test was applied for the normal distribution evaluation of the study and it was found that the continuous data fit the normal distribution. Descriptive statistical analyses (arithmetic mean, standard deviation, frequency, percentage), Student-t test, Pearson Chi-Square, Likelihood Ratio tests were used to evaluate the data. Bonferroni correction was used in post-hoc analyses. Further analyses were performed by Binary Logistic regression analysis.

In the logistic regression analysis, categorical variables (regular medication use and the presence of leg pain while standing) were entered into the model as binary variables (yes = 1, no = 0). Blood pressure measurements (SBP in the supine/sitting position and systolic and diastolic blood pressure at the 3rd minute of standing) were analyzed as continuous variables. The odds ratios calculated for continuous variables represent the effect of a 1-mmHg increase in the corresponding variable on the likelihood of OH. The significance level was accepted as p ≤ 0.05. The power of the study was found to be 0.98 by using the G-Power programme, with an effect size of 0.3 (medium) and an alpha of 0.05. G-Power calculation was based on chi-square test.

Results

Sociodemographic and health status related characteristics of the participants

The mean age of the older adults hospitalised in the internal medicine clinic who participated in our study was 74.1 ± 8.5 years. More than half of the participants were male (57.7%), most of them had chronic diseases (89.8%) and used regular medication (80.4%). Individuals who reported experiencing symptoms when standing up from a lying position during the day were 60% of the participants (Table 1). Regularly used medications included angiotensin-converting enzyme inhibitors, beta-blockers, diuretics, antidiabetics, bronchodilators and other drugs. OH occurred in 14.3% (n = 38) of 265 older adults. A total of 147 participants were assessed using the sit-to-stand test, and OH was identified in 17 individuals (44.7%). In contrast, 118 participants were evaluated using the supine-to-standing test, among whom orthostatic hypotension was detected in 21 individuals (55.3%).

Table 1.

Comparison of sociodemographic and health status-related characteristics of participants with and without orthostatic hypotension

Characteristics	Total			OH (Yes)		OH (No)
		n	%	n	%	n	%	Test, p
Gender	Female	112	42.3	19	50.0	93	40.9	*1.088;0.297
	Male	153	57.7	19	50.0	134	59.1
Body mass index	Normal	68	25.7	8	21.1	60	26.4	*0.517;0.775
	Overweight	129	48.6	20	52.6	109	48.1
	Obesity	68	25.7	10	26.3	58	25.5
Presence of chronic disease	No	27	10.2	1	2.6	26	11.5	*3.654;0.056
	Yes	238	89.8	37	97.4	201	88.5
Presence of chronic kidney disease	No	212	89.1	29	78.4	183	91.0	*4.350;0.037
	Yes	26	10.9	8	21.6	18	9.0
Duration of chronic disease	1–5 years	46	19.3	6	16.2	40	19.9	*7.723;0.060
	6–10 years	54	22.7	14	37.8	40	19.9
	11–20 years	101	42.4	10	27.1	91	45.3
	21 years and above	37	15.5	7	18.9	30	14.9
Regular use of medicines	No	52	19.6	3	7.9	49	21.6	*3.869;0.049
	Yes	213	80.4	35	92.1	178	78.4
Diuretic use	No	93	43.7	9	25.7	84	47.2	*5.485; 0.019
	Yes	120	56.3	26	74.3	94	52.8
Experiencing symptoms when standing up from a sitting/lying position during the day	No	106	40.0	12	31.6	94	41.4	*1.311;0.252
	Yes	159	60.0	26	68.4	133	58.6
Age	X±SS	74,1±8,5		X±SS		X±SS		t;p
				74,1±5,9		73,6±6,3		*0.481;0.631

*Chi-square Likelihood Ratio, p<0.05, OH Orthostatic Hypotension

Participants with and without OH were compared with respect to gender, age, presence of chronic disease, regular medication use, and symptom experience when standing up at any time during the day. The presence of chronic kidney disease (p = 0.037), frequency of regular medication use (p = 0.049) and diuretic use (p = 0.019) were higher in participants with OH compared to those without OH. No significant difference was found between other variables and the presence of OH (p > 0.05) (Table 1).

Symptoms that participants reported experiencing when standing up during the day

Older adults who reported experiencing symptoms when they stood up during the day reported that the most common symptoms were “darkening eyesight upon standing” (73.0%) and “dizzy spell” (81.8%). The frequency of those who reported “feeling faint” when standing up during the day was found to be significantly higher in participants with OH compared to those without OH (p = 0.048). The frequency of participants with OH who reported leg pain while standing at any time during the day was significantly higher than those without OH (p = 0.009) (Table 2).

Table 2.

Comparison of symptoms experienced by participants with and without orthostatic hypotension when standing up at any time during the day

Symptoms	OH assessment in individuals with symptoms
	OH (Yes)	OH (No)	test; p
	%	%
Dizziness	14.8	85.2	*0.141;0.707
Darkening eyesight upon standing	14.7	85.3	*0.903;0.342
Feeling faint (presyncope)	30.4	69.6	**3.899;0.048
Dizzy spell	16.9	83.1	**0.176;0.675
Difficulty breathing	29.4	70.6	**2.057;0.152

Other Symptoms	OH assessment in individuals with symptoms
	OH (Yes)	OH (No)	test; p
	%	%
Sprain/weakness in the legs	17.5	82.5	*1.349;0.245
Feeling leg pain when standing	23.1	76.9	*6.870;0.009
History of falling	19.6	80.4	*1.427;0.232

^*Pearson Chi-Square

^** Chi-square Likelihood Ratio, p < 0,05, OH Orthostatic Hypotension

Distribution of participants' pain score, pulse rate, systolic, and diastolic blood pressure measurements

Older adults with OH had higher SBP values in the supine position (p < 0.001) and significantly lower SBP and DBP values in the third minute after standing up compared to those without OH (p < 0.001; p < 0.001). No significant difference was found between other variables and the presence of OH (p > 0.05) (Table 3).

Table 3.

Comparison of pain score, pulse rate, systolic and diastolic blood pressure measurements of participants with and without orthostatic hypotension*

Characteristics	Total	OH (Yes)	OH (No)
	X ± SS	X ± SS	X ± SS	t;p
Pain score	6.3 ± 1.7	6.3 ± 2.1	6.3 ± 1.6	0.083;0.934
Pulse rate	79.0 ± 10.0	79 ± 12	79 ± 9	0.015;0.988
SBP in supine/sitting position	120.3 ± 10.1	126.8 ± 9.0	119.3 ± 9.9	4.429; < 0.001
DBP in supine/sitting position	73.3 ± 7.3	73.7 ± 6.3	73.5 ± 7.5	0.159;0.874
SBP at 1 min in standing position	117.2 ± 9.8	117.37 ± 9.5	117.2 ± 9.8	0.110;0.913
DBP at 1 min in standing position	70.8 ± 7.7	69.74 ± 6.8	71.0 ± 7.8	0.947;0.345
SBP at 3 min in standing position	114.8 ± 10.1	107.4 ± 8.5	116.0 ± 9.8	5.121; < 0.001
DBP at 3 min in standing position	68.2 ± 8.1	63.3 ± 7.4	69.0 ± 7.98	4.148; < 0.001

^*Since the dependent variables were continuous, regression was not performed with this table and adjusted OR was not taken. Student-t test, p < 0,05, SBP Systolic Blood Pressure, DBP Diastolic Blood Pressure, OH Orthostatic Hypotension

Investigation of conditions that may affect participants' orthostatic hypotension

According to logistic regression analysis, participants who reported leg pain while standing were significantly associated with OH (OR = 2.51; 95% CI: 1.24–5.05; p = 0.010). A statistically non-significant but increasing trend was observed in the association between regular medication use and OH (OR = 3.21; 95% CI: 0.95–10.89; p = 0.061). When continuous variables were evaluated, each 1 mmHg increase in SBP in the supine/sitting position was associated with OH (OR = 1.08; p < 0.001). In contrast, higher SBP at 3 min of standing was inversely associated with OH (OR = 0.91; p < 0.001). DBP at 3 min of standing also showed a significant association with OH (Tables 4 and 5).

Table 4.

Factors that may affect the occurrence of orthostatic hypotension in participants

Logistic regression analysis of ordinal variables that may have an effect on participants' having orthostatic hypotension
		B	S.E	Wald	df	Sig	Exp (B)	95.0% C.I.for EXP (B)
								Lower	Upper
Step 1(a)	Regular use of medicines (1)	1.167	0.623	3.509	1	0.061	3.212	0.947	10.886
	Feeling leg pain when standing (1)	0.918	0.358	6.577	1	0.010	2.505	1.242	5.054

^aVariable(s) entered on step 1: Regular use of medicines (1), Feeling leg pain when standing (1), Logistic Regression (Binary) Analysis, Values shown with ‘Exp (B)’ include adjusted OR values

Table 5.

Factors that may affect the occurrence of orthostatic hypotension in participants

Logistic regression analysis of continuous variables that may have an effect on participants' having orthostatic hypotension
Step 1(a)		B	S.E	Wald	df	Sig	Exp (B)	95.0% C.I.for EXP(B)
								Lower	Upper
	SBP in supine/sitting position	0.074	0.018	16.609	1	< 0.001	1.077	1.039	1.116
	SBP at 3 min in standing position	−0.099	0.021	21.616	1	< 0.001	0.906	0.869	0.944
	DBP at 3 min standing position	−0.106	0.027	15.015	1	< 0.001	1.112	1.054	1.174

^aVariable(s) entered on step 1: Systolic Blood Pressure in supine/sitting position, Systolic Blood Pressure at 3 min in standing position, Diastolic blood pressure at 3 min standing position, Logistic Regression (Binary) Analysis, Values shown with ‘Exp (B)’ include adjusted OR values

Discussion

In this study, factors predicting OH in older adults, a topic that will never lose its importance, were addressed by nurses. Evaluation of OH, especially by nurses, is very important in terms of prevention of OH-related complications.

In our study, the rate of OH was similar to the rate of OH in older adults reported in the literature 9.6–16% [11, 55, 58, 61, 72]. In the literature, it is reported that OH is less common in the evening hours compared to the morning and afternoon [69]. In this study, measurements were performed mostly in the afternoon due to compulsory reasons.

In our study, individuals who were not suitable for assessment using the supine-to-standing test were evaluated with the sit-to-stand test. Shaw et al. [60] emphasized that the sit-to-stand test may enable OH assessment, particularly in situations where the supine-to-standing test cannot be easily performed. According to this perspective, the smaller blood pressure change induced by a maneuver performed from the sitting position may be considered comparable to the larger change induced by a maneuver performed from the supine position. However, there is no consensus in the literature regarding whether the 15/7 mmHg cutoff values are optimal for OH assessment using the sit-to-stand test, and several studies do not support this threshold [21, 30]. Gabriele et al., [21] found that orthostatic blood pressure changes are more pronounced in the frailest patients when going from lying to the upright position than from the sitting to the upright position. They also stated that lying and sitting blood pressure measurements should not be considered interchangeable baseline positions when assessing orthostatic blood pressure responses [21]. Although the number of individuals assessed using the supine-to-standing test was smaller in our study (n = 118), a higher frequency of OH was observed in this group. This finding is consistent with the view that the supine-to-standing test may be considered the gold standard for OH assessment. Our results also suggest that the sit-to-stand test may underestimate OH due to its lower orthostatic stress, potentially limiting the ability to reach traditional blood pressure thresholds for diagnosis [1]. However, the detection of OH in 44.7% of older adults using this method suggests that, while it does not replace the supine-to-standing test, it may serve as a practical alternative when the latter cannot be performed. Accordingly, the question of whether the sit-to-stand test is appropriate for hospitalized patients, in whom OH assessment using the supine-to-standing test is expected to be difficult, may remain clinically relevant.

We found that the presence of chronic kidney disease, regular use of medication and diuretic use were higher in older adults with OH compared to those without OH. It has been reported that chronic kidney disease and diuretic use are factors that may have a direct effect on fluid volüme [31]. A similar study found an association between chronic kidney disease and OH in hospitalized older adults [7]. One study found that diuretic use was one of the determinants of OH in individuals with chronic kidney disease [27]. The higher frequency of diuretic use in adults- with OH in our study may be explained by the fact that diuretics are considered to be one of the main determinants of drug-related OH. By increasing urinary sodium excretion, diuretics may predispose to volume depletion and OH, especially in older adults [54]. Since OH occurs as an abnormal response to changes in the body's fluid balance while standing [53], individuals with OH may be more sensitive to fluid volume imbalances due to the presence of chronic kidney disease and regular use of diuretic drugs. Considering that OH may be associated with impaired renal function independent of age, gender and high blood pressure [12], the results of our study may highlight the importance of the relationship between OH and kidney function in older adults. Awareness of this relationship may facilitate early recognition of OH in older adults with chronic kidney disease and improve OH-related healthcare outcomes.

In the literature, it has been suggested that the presence of symptoms should be considered during the evaluation of OH [13, 23]. In the present study, symptom assessment was conducted both during blood pressure measurements and at any time during the day. OH-related symptoms were reported by a proportion of participants with OH,however, among these symptoms, only the frequency of feeling faint appeared to be more commonly reported in individuals with OH compared to those without OH. Although symptoms such as fatigue, reduced alertness, emotional changes, dizziness, and lightheadedness have been described in association with OH [13, 38], previous studies have also indicated that postural blood pressure reductions are often not accompanied by subjective symptoms [35]. In this context, it may be considered that individuals with OH do not necessarily differ from those without OH in terms of the overall presence of OH-related symptoms. Conversely, previous literature has highlighted that symptoms such as dizziness or near-syncope may have greater clinical relevance than blood pressure changes alone [25]. In this context, the findings of the present study may indicate that reports of feeling faint when standing are observed more frequently among older adults with OH and could be considered during OH evaluation. At the same time, these findings highlight that the absence of typical symptoms such as dizziness does not necessarily preclude the presence of OH and that OH assessment may also be relevant in asymptomatic individuals.

In our study, the frequency of participants with OH who stated that they felt leg pain while standing during the day was significantly higher than those without OH. It was determined that experiencing leg pain while standing had the potential to increase the risk of orthostatic hypotension by 2.5 times. The literature emphasizes that OH may be asymptomatic in the majority of patients, while in some cases it may manifest with symptoms such as shoulder, neck, or low back pain [17, 19, 44, 62]. Lower extremity muscle pain and weakness, which are commonly observed in many patients, have been associated with postural orthostatic tachycardia syndrome (POTS) [2]. This association has been interpreted as resulting from varying degrees of sympathetic denervation that impair reflex vasoconstriction during standing, thereby contributing to excessive venous pooling and leading to these lower extremity symptoms [2]. In the present study, patients were not evaluated for POTS. However, Arnold and Navarro-Otano [2] highlighted the importance of investigating whether similar alterations in muscle membrane properties are observed in patients with chronic and severe orthostatic venous pooling caused by OH. Prioritizing the assessment of OH may be beneficial, particularly in older adults who experience leg pain during the day; however, high-quality, high-level evidence studies are required to substantiate this approach.

In this study, heart rate measurements were assessed only once (before starting blood pressure assessments). The literature describes age-related changes in the phased heart rate and blood pressure responses to orthostatic stress. With advancing age, the maximum increase in heart rate during the initial phase and the ratio between the maximum and minimum heart rates may decline; consequently, a relatively stable heart rate may be observed regardless of posture. Particularly in active, well-hydrated, and normotensive older adults, blood pressure and cardiac output may be preserved through compensatory mechanisms even if the heart rate response to standing is attenuated [32]. However, it is noted that in older adults with impaired baroreceptor function, physiological tachycardia may not occur in response to significant fluid loss [24, 34]. In neurogenic OH, it is emphasized that compensatory mechanisms may fail to be adequately activated due to impaired baroreflex function, a condition that may be most evident in the absence of an increase in heart rate [8]. In our study, heart rate measurements were not evaluated during positional changes. Consequently, it was not possible to distinguish neurogenic OH from non-neurogenic OH. This represents one of the limitations of our study.

We observed that older adults with OH tended to have higher supine SBP values and lower standing SBP and DBP values at three minutes compared with those without OH. In the literature, it has been suggested that adjusting OH diagnostic criteria according to baseline supine SBP may help improve clinical accuracy [12]. The literature indicates that, particularly in the absence of blood pressure–lowering medications, classical OH is often of neurogenic origin, and that in approximately half of patients with neurogenic OH this condition coincides with supine hypertension [10],however, it has been emphasized that the mechanisms underlying this complication are not yet fully understood [46, 66]. The higher blood pressure values observed in the supine/sitting positions in our study did not refer to values meeting or exceeding the diagnostic thresholds for hypertension. As a neurogenic distinction could not be made, our findings may merely draw attention to the need not to overlook individuals with relatively higher supine/sitting blood pressure values when assessing OH. In our study, we observed that higher DBP values at 3 min while standing were associated with a possible 11.2% increase in OH, whereas higher SBP values at 3 min while standing were associated with a possible 9.4% decrease in OH. The literature suggests that an increase in DBP while standing may be a normal finding. It also indicates that cardiac stroke volume may decrease in individuals with an excessive orthostatic increase in heart rate, making the interpretation of apparent increases in DBP challenging [28]. As postural orthostatic tachycardia was not assessed in the participants of our study, interpreting the potential associations between higher DBP values while standing and OH may be challenging. In the literature, it is emphasized that diastolic OH should be paid more attention in older adults [69]. We recommend that DBP should be specifically investigated in future studies to be planned in older adults.

As OH in older adults is associated with a higher risk of falls, fractures, dementia and mortality, it is important to recognize and treat it urgently. The literature suggests that medication alone is certainly not enough [15], and factors associated with OH should be addressed by health professionals [72]. As orthostatic stress varies according to conditions during the day, a patient-focused approach emphasizing education and non-pharmacological strategies is critical. In particular, it is stated that it is important to be able to improve standing time, symptoms during standing, and thus the capacity to perform daily functions while standing [15]. We think that our study results will provide an up-to-date contribution to the literature on taking necessary precautions by emphasizing the importance of OH in older adults.

Limitations

This study had some limitations. First of all, the study was conducted in a single centre due to the lack of qualified human resources, the duration of the study and funding constraints. Data were collected according to the availability of the researcher. Therefore, blood pressure measurements were mostly performed in the afternoon. This may limit the generalizability of the study results. Blood pressure measurements may be preferentially performed in the morning hours, as OH symptoms have been reported to be more pronounced during this period. However, the findings of the current study suggest that OH assessment at different times of the day may also be informative. Another limitation of this study was the methodological heterogeneity resulting from the use of different assessment methods; while many participants were evaluated using the supine-to-standing test, a larger proportion were assessed using the sit-to-stand test. Although the sit-to-stand test may be considered a practical alternative when other assessment methods cannot be applied, this heterogeneity may have influenced the accurate identification of older adults with OH. Finally, as this was a cross-sectional study, the findings indicate associations between variables but do not allow for causal inferences or predictive conclusions.

Conclusions

Orthostatic hypotension was observed in approximately one in seven older adults hospitalized in internal medicine clinics. The presence of leg pain while standing during the day and a one-unit increase in SBP in the supine position may be associated with an increased likelihood of OH. Accordingly, the observation of blood pressure values within a safe range in the supine position in older adults should not necessarily be interpreted as indicating that OH will not occur.

In addition, our findings suggest a potential association between OH and renal function in older adults. Increased awareness of this relationship may contribute to earlier recognition of OH in individuals with chronic kidney disease and could potentially improve OH-related healthcare outcomes.

Based on the findings of this study, the following considerations may be proposed:

• Risk assessment for OH in older adults hospitalized in clinical settings may be beneficial, with attention to individual-specific factors.

• Older adults who report leg pain while standing during the day may warrant closer monitoring for the risk of OH, and appropriate pain management could be considered.

Authors’ contributions

H.A. contributed to designed the research framework manuscript preparation, collected the data, participated in manuscript writing, guided data interpretation, supported literature review. All authors reviewed, edited, and approved of the final manuscript and agreed to be accountable for its accuracy and integrity. S.K. conceptualized the study, designed the research framework, supervised all stages of the project, contributed to study design, participated in manuscript writing, guided data interpretation, supported literature review, contributed to manuscript preparation, contributed to manuscript editing, and facilitated ethical approval.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or non-profit sectors.

Data availability

The data that support the findings of the study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

The study followed the Declaration of Helsinki and was approved by the Ethics Committee of Nursing Faculty of Aydın Adnan Menderes University (Protocol Number: 2023–359 – Approval Date: 07.31.2023 – Decision No: VI). Official permission was obtained from the institution where the study was conducted before starting the study. Written informed consent was obtained from all participants after they were fully informed about the study’s purpose and procedures. In addition, they were informed that they could withdraw from the study at any time without any negative consequences.

Consent for publication

This manuscript does not include any identifying images or personal/clinical details of participants that compromise anonymity.

Competing interests

The authors declare no competing interests.