Association Between Sleep Quality and Geriatric Hip Fracture: A Prospective Comparative Study

Abstract

Background

The aim of this study was to evaluate the association between sleep disturbance and geriatric hip fracture.

Methods

Between January 2023 and August 2024, 90 patients admitted to the Adult Emergency Clinic with the diagnosis of hip fracture were included in the study. In addition, a control group consisted of 90 patients, aged ≥65 years, and undergoing elective orthopedic surgery without prior hip fracture. The Pittsburg Sleep Quality Index (PSQI) test, Bone Mineral Densitometry and Vitamin D and Calcium levels were examined and noted in the inpatient service for both groups of patients two days after surgery.

Results

A total of 180 patients were included. The fracture group demonstrated higher PSQI scores compared with the control group (6.74 ± 4.02 vs 5.23 ± 3.06, p=0.005). Poor sleep quality (PSQI >5) was more frequent in the fracture group (73.3% vs 33.3%, p<0.001). Serum calcium levels were lower in the fracture group (p<0.001), while vitamin D and DEXA scores were not significantly different (p=0.796 and p=0.119, respectively). Within the fracture cohort, poorer sleep quality was associated with older age and female sex.

Conclusion

Geriatric hip fracture patients demonstrated poorer sleep quality compared with elective surgical control patients. Screening for sleep problems could help identify high-risk geriatric individuals who may benefit from comprehensive fall-prevention strategies.

Keywords

sleep hip fracture geriatric osteoporosis femur

Introduction

Geriatric hip fractures are more common as the elderly population increases.¹ As life expectancy continues to increase worldwide, a better understanding of why hip fractures occur and how to prevent further injuries should be the overall focus, as increasing cases place a growing burden on healthcare resources and worsen the already significant personal and societal costs associated with these injuries.² Consequently, there is an urgent need for effective preventive measures to reduce the incidence and impact of hip fractures in the elderly population.

Sleep disorders are associated with different consequences, including musculoskeletal pain and physical dysfunction.^3-5 Prior research has shown correlations between naps, short sleep duration, excessive daytime sleepiness, and a higher likelihood of falling.^5-8 Sleep disturbances can also have an indirect impact on fractures and falls through several other pathways, such as depression, vitamin D deficiency, and cognitive impairment.⁹ Recent meta-analyses have also shown that sleep duration is additionally associated with osteoporosis.^10,11 Overall, up to 69% of older individuals report sleep disorders.³ The Pittsburgh Sleep Quality Index (PSQI), created in 1988 without a specific clinical population in mind, was designed to provide a reliable, valid, and standardized assessment of sleep quality, distinguish between good and poor sleepers, and offer an easy-to-use tool for patients, clinicians, and researchers.¹² The PSQI is the most widely used test in clinical practice and research.¹³

The etiology of hip fractures in the elderly is multifactorial, encompassing a complex interplay of intrinsic and extrinsic factors. Most hip fractures are caused by osteoporosis and fall injuries in daily life activities.¹⁴ It may be hypothesized that sleep problems are associated with fracture vulnerability, although causality remains uncertain.

The current study aimed to evaluate the association between sleep disturbance and geriatric hip fracture. We hypothesized that sleep quality would differ between patients with hip fractures and elective surgical controls. The main purpose of this study is to measure sleep quality in geriatric patients and explore its potential use as a screening tool to identify those at higher risk of falls or fractures.

Materials and Methods

This study employed a prospective comparative observational design to analyze the sleep quality of geriatric hip fracture patients. The study was initiated after the ethics committee approval was obtained from local ethics committee (Ek1 2023-576). Written informed consent was obtained from each patient. Patients admitted to the Adult Emergency Clinic with the diagnosis of hip fracture between January 2023 and August 2024 are listed. Age, sex and fracture type were noted. Inclusion criteria were determined as patients over the age of 65 who applied to the adult emergency clinic with a hip fracture, patients who could complete the PSQI,¹² and patients who agreed to have a Bone Mineral Densitometry measurement. Patients with neurological diseases such as dementia and Alzheimer’s disease, and patients who were contacted with the help of their relatives, were excluded from the study. 90 patients with intertrochanteric and femoral neck fractures were included in the study. For fracture patients, time from hospital admission to surgery was recorded and analyzed. In addition, a control group consisted of 90 geriatric patients hospitalized for elective primary osteoarthritis surgery, including total hip arthroplasty or total knee arthroplasty. Patients with a history of hip fracture were excluded from the control group. The PSQI test,¹² Bone Mineral Densitometry and Vitamin D and Calcium levels were examined and noted in the inpatient service for both groups of patients two days after surgery.

Perioperative Management and Analgesia Protocol

All patients received regional anesthesia using the same institutional protocol. Postoperative analgesia was standardized in both groups and consisted of multimodal analgesia including paracetamol and non-steroidal anti-inflammatory drugs, with opioids administered only as rescue medication.

Mobilization Protocol

All patients were mobilized on postoperative day 1. Patients in the elective arthroplasty group were mobilized with weight bearing as tolerated. Patients in the fracture group were mobilized according to fixation stability; individuals treated with internal fixation were mobilized without weight bearing on the operated extremity, while arthroplasty patients were mobilized with weight bearing as tolerated.

Statistical Analysis

Statistical analysis was performed in the Statistical Package for the Social Sciences (SPSS) 22 package program. To determine differences between groups with numerical variables; Independent Sample t test for variables that provide normality distribution; Mann Whitney U Test was run for variables that could not be provided. Chi-Square Test, a non-parametric test, was started to be used to analyze the differences between groups for categorical variables. In analyzes regarding groups with more than 2 categories, Post Hoc Analysis was performed to determine which groups had a significant difference. This capability is the Corrected Residual detection configuration; new p values were detected with Bonferroni correction. The change and interpretation of differences between groups were made according to these p values. The results of the tests performed on the variables in the study were evaluated within the 95% confidence interval, and a p value of <0.05 was considered significant.

Results

A total of 180 patients included in the study were divided into two groups: control (n = 90) and fracture (n = 90) groups. The average age of the patients is 75.7 ± 8.93 years. The length of hospital stay was similar between the fracture and control groups (6.8 ± 1.7 vs 5.5 ± 1.9 days, p = 0.34). The mean time from admission to surgery in the hip fracture group was 31.6 ± 18.3 hours. The PSQI (Pittsburg Sleep Quality Index) total score average was recorded as 5.98 ± 3.64, and the DEXA (Dual-Energy X-ray Absorptiometry) total score average was recorded as -1.97 ± 0.93. Calcium and Vitamin D levels were found to be 9.08 ± 0.66 mg/dL and 57.26 ± 31.74 ng/mL, respectively. Patients in both groups were compared in terms of demographic, clinical-laboratory and sleep characteristics, and the distribution of the results is shown in Table 1. Baseline comorbidity characteristics were comparable between the groups (Table 2).

Table 1.

Demographic Characteristics of the Study

	Total patients n=180	Group 1 (fracture group) n=90	Group 2 (control group) n=90	P value
Age	75.7 ± 8.93	70.9 ± 6.01	80.4 ± 8.87	<0.001
Gender (M/F)	120/60	58/32	62/28	0.527
Hospital Length of Stay (SD)	6.15 ± 1.91	6.8 ± 1.7	5.5 ± 1.9	0.34
PSQI (GQ/BQ)	96/84	66/24	30/60	<0.001
BMD (N/Osteopenia/Osteoporosis)	35/93/52	12/56/22	23/37/30	0.014
PSQI Total Score	5.98 ± 3.64	5.23 ± 3.06	6.74 ± 4.02	0.005
BMD Total Score	-1.97 ± 0.93	-1.86 ± 0.96	-2.08 ± 0.88	0.119
Calcium Blood Level	9.08 ± 0.66	9.32 ± 0.65	8.85 ± 0.59	0.000
Vitamin D Blood Level	57.26 ± 31.74	51.4 ± 15.6	63.1 ± 41.3	0.796

Table 2.

Baseline Demographic and Clinical Characteristics of the Study Groups

Variable	Hip fracture (n=90)	Control (n=90)	Total (n=180)	p-value
ASA score ≥3, n (%)	41 (45.6%)	38 (42.2%)	79 (43.9%)	0.67
Diabetes mellitus, n (%)	28 (31.1%)	25 (27.8%)	53 (29.4%)	0.64
Hypertension, n (%)	55 (61.1%)	52 (57.8%)	107 (59.4%)	0.67
Coronary artery disease, n (%)	24 (26.7%)	21 (23.3%)	45 (25.0%)	0.61
Polypharmacy (>5 medications), n (%)	36 (40.0%)	34 (37.8%)	70 (38.9%)	0.78

Comparisons Between Control and Fracture Groups

The average age of the control group was 70.9 ± 6.01, this average was found to be significantly higher in the fracture group (80.4 ± 8.87, p <0.001). Gender distribution did not show a significant difference between the fracture and control groups (p = 0.527).

In determining the relationship between geriatric hip fracture and sleep disturbance, the groups were examined by taking both the PSQI mean score and cutoff value as reference and a comparison was made between the two groups. The mean PSQI total score of the fracture group (6.74 ± 4.02) was found to be significantly higher than the control group (5.23 ± 3.06, p = 0.005). In terms of the cutoff variable, 73.3% of the patients in the fracture group experienced poor quality sleep; Poor quality sleep was determined to be lower in control group patients (33.3%, p <0.001).

Other variables examined in our study are serum calcium level, DEXA and vitamin D levels, respectively. While the average serum calcium value was 8.85 in the fracture group, this value was calculated as 9.32 in the control group and was found to be lower in the geriatric hip fracture group (p <0.001). The mean of the fracture group was found to be -2.08 ± 0.88, and the mean of the control group was -1.86 ± 0.96, but the difference between the groups was not statistically significant (p = 0.119). Vitamin D levels were not found to be different between the groups (p = 0.796).

In our study, since the groups were independent from each other and the numerical variables showed normal distribution, patients in the fracture group were also examined for their relationships with other variables according to the PSQI cut-off value. For this purpose, the fracture group was divided into two subgroups as ‘good quality’ and ‘bad quality’ according to sleep quality, and their relationships with age, gender, DEXA mean value, time to fall, fracture type, serum calcium and vitamin D levels were investigated (Table 3).

Table 3.

Relationships With Other Variables According to the PSQI Cut-Off Value in Fracture Group

	PSQI (bad quality)	PSQI (good quality)	P value
Age	81.8 ± 8.64	76.7 ± 8.61	0.017
Gender (M/F)	27.3%/72.7% (n=48/18)	58.3%/41.7% (n=10/14)	0.006
PSQI total value	8.31 ± 3.5	2.41 ± 1.21	0.000
DEXA	-2.16 ± 0.87	-1.84 ± 0.91	0.123
DEXA cutoff (N/Osteopenia/Osteoporosis)	12.1%/60.6%/27.3% (n=8/40/18)	16.7%/66.7%/16.7% (n=4/16/4)	0.553
Calcium Blood Level	8.83 ± 0.62	8.93 ± 0.50	0.471
Vitamin D Blood Level	65.6 ± 34.6	56.0 ± 26.3	0.841
Time to Fall (Daytime/Nighttime)	66.7%/33.3% (n=44/22)	58.3%/41.7% (n=14/10)	0.465
Fracture type (Femoral Neck Fracture/Pertrochanteric Fracture)	27.3%/72.7% (n=18/48)	8.3%/91.7% (n=2/22)	0.05

The “PSQI Bad Quality” group had a significantly older average age (81.8 ± 8.64) compared to the “PSQI Good Quality” group (76.7 ± 8.61, p=0.017). A significant gender difference was found between the two groups. The “PSQI Bad Quality” group consisted of 27.3% males and 72.7% females (n = 48/18), while the “PSQI Good Quality” group had a more balanced distribution, with 58.3% males and 41.7% females (n = 10/14). This difference was statistically significant (p = 0.006). A significant difference was found in the type of fracture between the two groups (p = 0.050). The “PSQI Bad Quality” group had a higher proportion of femoral neck fractures (27.3%) compared to the “PSQI Good Quality” group (8.3%). Conversely, 91.7% of fractures in the “PSQI Good Quality” group were pertrochanteric fractures, compared to 72.7% in the “PSQI Bad Quality” group.

No significant difference in DEXA scores was observed between the two groups (p = 0.123). The “PSQI Bad Quality” group had a mean DEXA score of -2.16 ± 0.87, while the “PSQI Good Quality” group had a mean score of -1.84 ± 0.91. The average calcium levels did not differ significantly between PSQI subgroups (p = 0.471). No significant difference was observed in vitamin D levels between the two groups (p = 0.841). The time of the fall (daytime vs. nighttime) was not significantly different between the groups (p = 0.465). In the “PSQI Bad Quality” group, 66.7% of falls occurred during the daytime, while 33.3% occurred at night. In the “PSQI Good Quality” group, 58.3% of falls occurred during the daytime and 41.7% at night.

Discussion

The present study compared sleep quality between geriatric hip fracture patients and elective orthopedic surgical controls. The principal finding was that hip fracture patients demonstrated poorer sleep profiles and a higher prevalence of poor sleep quality according to the PSQI.

It is of great importance for all healthcare practitioners to identify possible risk factors in the management of geriatric hip fractures and thus reduce the negative effects of these fractures.^2,15 Previous studies have suggested that sleep disturbances are associated with sarcopenia, impaired balance, and an increased likelihood of falls in elderly individuals. Because most geriatric hip fractures occur following low-energy falls, sleep disturbances may reflect an underlying frailty phenotype rather than directly causing fractures.¹⁶

This study, as far as we have investigated in the English literature, is the first study that includes a control group and shows that both the average sleep scores and sleep quality in the hip fracture group differ significantly compared to the control group. However, this finding should be interpreted with caution. Although statistically significant, the observed difference was small. The minimal clinically important difference (MCID) for PSQI is approximately 4.4 points, which exceeds the difference seen in our cohort. Therefore, at the individual level, the clinical impact may be limited, and sleep disturbances are better viewed as a marker of vulnerability at the population level rather than a direct cause of fractures.¹⁷

Considering similar studies, Rogers et al examined the likelihood of falling and its relationship with hip fracture in 3001 patients with circadian sleep disorders. In that study, irregular circadian disorders had a positive relationship with the likelihood of falling, but did not increase the risk of hip fracture.¹⁸ In a study conducted on 157 thousand elderly individuals, it was stated that poor sleep quality increased the risk of recurrent falls, but was not directly related to the risk of hip fracture.¹⁹ In a similar study, 34.163 healthy individuals over the age of 65 living in a nursing home were followed for 210 days, and the relationship between sleep disorders and the likelihood of falling - the risk of hip fracture was examined. It was stated that sleep disorders increased the likelihood of falling, but did not show a significant relationship with hip fracture.²⁰ Our findings are consistent with this concept and support the idea that sleep disturbances are associated with fall susceptibility, which is a key factor in geriatric hip fractures.

The relationship between bone mineral density and geriatric hip fractures is well known. The hypothesis that sleep disorders may affect bone mineral density and therefore the risk of osteoporotic fractures is a subject that many researchers have studied. Literature shows that sleep abnormalities have a negative impact on bone mineral density, associated with obesity, insulin resistance and insufficient physical activity. Furthermore, disrupted sleep has been linked to metabolic and hormonal changes, including altered melatonin and cortisol levels, which are also associated with bone density and fracture risk.^21-24 In our research, the fracture group was divided into two groups, good and bad sleep, and compared in terms of DEXA average and DEXA cut-off values. According to the data obtained, our study did not find a statistically significant difference in BMD between groups, suggesting that fracture occurrence in this population is not solely attributable to bone fragility and may instead reflect factors such as functional decline and increased fall risk. This finding differs from some previous studies regarding the role of low BMD in fracture risk.

Epidemiological studies have shown the relationship between serum vitamin D and sleep quality and balance.^25-27 Vitamin D supplementation was shown to improve sleep quality in individuals with sleep disorders.²⁸ Additionally, there are studies showing that vitamin D improves muscle strength and function through calcium metabolism, thus reducing both the risk of falling.^23,28,29 In a meta-analysis examining 31 randomized controlled studies, it was reported that individuals with serum D-vitamin levels lower than 50 nmol/L had a 23% higher risk of falling.³⁰ Accompanied by these data, many researchers have conducted various studies, deriving the hypothesis that vitamin D deficiency has a negative effect on sleep quality and muscle strength, increasing both the likelihood of falling and the risk of fractures in the elderly population. In our study, no relationship was found between serum vitamin D levels, sleep quality and hip fracture. We think that the reason why serum vitamin D levels are not associated with both sleep disturbance and fracture risk is that the average values of both groups are higher than 50 nmol/L.

Analysis of the fracture group based on sleep quality revealed additional insights. Within the fracture cohort, poorer sleepers were older and more frequently female, in line with established epidemiologic patterns of frailty and fracture susceptibility. The higher proportion of femoral neck fractures among poorer sleepers may reflect differences in fall mechanics rather than bone quality alone.

This study has several strengths. The inclusion of a hospitalized control group allowed comparison within a clinically relevant geriatric population. Additionally, multiple parameters related to bone metabolism were evaluated simultaneously. However, several limitations should be acknowledged. First, the observational design precludes establishing causality. Second, sleep quality was assessed during hospitalization and may have been influenced by the acute medical condition or perioperative environment. Third, no prior sample size calculation was performed, and the sample size limits statistical power; therefore, the study should be considered exploratory and hypothesis-generating. Finally, while the control group consisted of hospitalized patients undergoing elective surgery, completely healthy community-dwelling older adults were not included. Therefore, the findings may not fully reflect sleep patterns in the general healthy geriatric population.

Conclusion

Geriatric hip fracture patients demonstrated poorer sleep quality compared with elective surgical controls. These findings indicate that sleep disturbances may reflect underlying patient vulnerability and susceptibility to falls rather than serving as an independent causal risk factor for fractures. Screening for sleep problems could help identify high-risk geriatric individuals who may benefit from comprehensive fall-prevention strategies. However, the impact of targeted sleep interventions on fracture reduction remains to be evaluated in future prospective studies.

Supplemental Material

Supplemental Material - Association Between Sleep Quality and Geriatric Hip Fracture: A Prospective Comparative Study

Supplemental Material for Association Between Sleep Quality and Geriatric Hip Fracture: A Prospective Comparative Study by Erkan Akgun, Kemal Sibar, Huseyin Emre Tepedelenlioglu, Yavuz Emre Aktasoglu, Halil Gok, Aytek Huseyin Celiksoz, and Abdulsamet Emet in Geriatric Orthopaedic Surgery & Rehabilitation.

Footnotes

Acknowledgments

The authors thank to all hospital workers for their high efforts.

ORCID iD

Abdulsamet Emet

Ethical Considerations

This study was conducted in compliance with the ethical standards of the 1964 Declaration of Helsinki and its later amendments. The study was approved by the Ankara Etlik City Hospital Ethics Committee, which belongs to the Ankara Etlik City Hospital, Turkey (Approval Number: Ek1-2023—576).

Consent to Participate

Informed consent was obtained from all participants included in the study.

Author Contributions

AE, EA, KS and HET conceived this study, designed tool and protocol. Data collection was undertaken by YEA. Initial analysis and data integration were undertaken by AE, EA and AHC undertook the initial draft of the manuscript, and HG and KS contributed substantially to subsequent drafts and revisions. All authors approved the final version of the manuscript.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Data Availability Statement

The data used and/or analyzed during the current study are available from the corresponding author on reasonable request.*

Supplemental Material

Supplemental material for this article is available online.

Appendix

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