Diabetes and Hip Fractures: an Important Underrepresented Topic in the Related Literature

Marks R*

Department of Health and Behavior Studies, Teachers College, Columbia University, USA

*Corresponding author: Marks R, Department of Health and Behavior Studies, Teachers College, Columbia University Box 114, 525W 120th Street, New York,

Received: February 13, 2015; Accepted: April 26, 2015; Published: May 06, 2015

Abstract

Diabetes prevalence is increasing rapidly among older populations, who are also at high risk for hip fractures. This article examines whether hip fracture risk is increased in the presence of a diabetes diagnosis, and if so what are the ramifications of this association. It also examines the risk factors for incurring a hip fracture in the presence of diabetes, and the increased risk of adverse outcomes experienced by hip fracture patients with diabetes. Possible implications of this body of literature include efforts to reduce the risk and burden of hip fractures among the elderly as well as the severity of diabetes, in general. This article which provides a synthesis of this topic may hence be of value to clinicians interested in preventing adverse diabetes outcomes, as well as those who strive to promote healthy aging and positive life quality among the elderly with either type 1 or type 2 diabetes.

Keywords: Bone diabetes; Falls; Fracture; Hip fracture; Type 1 and Type 2 diabetes

Introduction

Hip fractures are a well-established prominent cause of premature and excessive morbidity, as well as mortality among aging adults [1]. As well, type 2 diabetes, is an increasingly prevalent health problem among the older population, along with type 1 diabetes, and both forms affect multiple organs and body systems. This brief examines the role of diabetes in general, in increasing the risk of sustaining a hip fracture among the elderly. It also examines evidence for poor post surgical outcomes after hip fracture. As well, it examines what can be done to minimize this risk, given the finding diabetes clearly increases the risk for hip fractures [2], as well as the outcomes of hip fractures among the elderly quite negatively [3-6]. Based on the most recent data in the literature, the topics discussed in this review are hip fractures and their relationship to diabetes, diabetes and bone health, diabetes and falls injuries, and potential prevention strategies to offset hip fracture prevalence and severity among older adults. This effort was undertaken given the apparent lack of attention to the impact of diabetes on musculoskeletal health status, when compared to physical status and glycemic control issues alone. It was hypothesized that adults with both type 1 and type 2 diabetes are at higher risk for falls that lead to hip fractures, as well as poorer health outcomes. It was also believed there would be few publications drawing attention to the need for vigilance against this debilitating health condition in the current literature compared to the number of nutrition and physical activity related recommendations even though this information is quite compelling. Limited post hip fracture rehabilitation strategies that are modified in light of the impact of diabetes on this process were expected even though reasons for the increased hip fracture risk and poor outcomes in this group are largely modifiable factors.

The specific questions were:

Is there a consistent relationship between the presence of a diabetes diagnosis and the risk of incurring a hip fracture?
Is the literature on diabetes self-management focused to the same degree on preventing disabling falls and subsequent hip fractures compared to articles on glycemic control alone?
What are the risk factors for hip fractures among diabetics and are adults with diabetes who sustain hip fractures likely to experience worse outcomes than those with no diabetes?
Is there a concerted effort to translate what we know about the link between diabetes and hip fractures into clinical research and practice?

Methods

Data sources sought were those that might provide topical information and interrelated data on diabetes and hip fractures, the possible causes of hip fractures among diabetics, and the implications of diabetes for preventing hip fractures in the peer reviewed literature. Data sources used were those published in the English language and covering the years 1993-2014, located in Academic Search Complete, which yielded 237 articles, many of which were housed in Pubmed or Cihahl or both using the key works Diabetes and Hip fracture; Diabetes and Falls; Diabetes and Balance; Hip Fracture Epidemiology; Hip Fracture Outcomes. Due to the diversity of the literature a metaanalysis was not conducted, rather a narrative synthesis of the data from clinical studies, and systematic reviews was conducted.

Findings

Diabetes and hip fracture risk: The examination of whether diabetes type 1 or 2 or both increases the risk for hip fractures has proceeded for more than 15 years. As outlined in (Table 1), many of these studies have been prospective in nature with large samples and have tended to conclude people with diabetes are more likely to be at increased risk for hip fracture than not. Although these studies reported in (Table 1) do not clearly differentiate type 1 from type 2 diabetes in all cases, according to Hothersall et al. [7]. who recently examined the risk of incurring a hip fracture among patients ages 20- 84 years with either type I or type 2 diabetes in a national sample from Scotland, a substantial increase of risk of hip fracture is present among patients with type 1 diabetes, especially at higher ages, but not among patients with type 2 diabetes, except for a small risk among women. However, these data were extracted from a pre-collected data base and may not have exemplified confounding factors or how type 2 diabetes affects hip fractures, as this is often undetected, even if present. The results presented by Hothersall et al. [7]. were also inconsistent with those of Lipscombe et al. [8]. who showed older individuals with diabetes are at increased risk for hip fractures. Janhorbani et al. [2], similarly found type 1 as well as type 2 diabetes are associated with an increased risk of hip fracture among women, when comparing rates to women without diabetes.

Table 1: Studies conducted over the last 15 years linking either type 1 or type 2 diabetes and hip fracture.




  
    Authors 
    Study design 
    Sample 
    Finding 
  
  
    Ahmed et al. [36] 
    Prospective
    27,159 subjects were followed for 7 years 
    Hip fractures were associated    with diabetes especially type 1 diabetes
  
  
    Chen et al. [37] 
    Prospective 
    500, 868 diabetes patients
    Diabetes generally increased    hip fracture risk
  
  
    Forsen et al. [38] 
    Prospective 
    35,444 adults 
    Diabetes type 1 and 2 increase hip fracture 
  
  
    Holmberg    et al. [17] 
    Prospective 
    33,000 adults 
    Diabetes is a strong hip fracture risk factor 
  
  
    Janghorbani et al. [2] 
    Prospective 
    109,983 women 
    Type 1 + 2 diabetes increase hip fracture 
  
  
    Koh et al. [11] 
    Prospective
    63,257 patients
    Diabetes almost doubled risk for hip fracture
  
  
    Lipscombe et al. [8] 
    Retrospective
    197, 412 diabetes cases
    Adults with diabetes have higher hip fracture risk
  
  
    Miao et al. [39] 
    Prospective
    24,605 diabetes patients
    Type 1 diabetes increases hip fracture risk
  
  
    Nicomedus and 
      Folsom [34] 
    Prospective
    32,089 older women
    Diabetes increases risk for hip fracture
  
  
    Ottenbacher et al. [40] 
    Prospective
    3050 older adults
    Diabetes is related to increased hip fracture
  
  
    Scwartz et al. [41] 
    3 Prospective studies
    1969 adults
    Type 2 diabetes may present hip fracture risk
  
  
    Segal et al. [42] 
    Case-control
    142 hip fracture cases
    Diabetic patients have increased hip fracture
  
  
    Strotmeyer et al. [13] 
    Cross-sectional
    5888 older adults
    Type 2 diabetes was related to hip fractures
  
  
    Tal et al. [43] 
    Prospective
    1161 older adults
    Diabetes increases trochanteric fracture risk
  
  
    Vestergaard et al. [70] 
    Case-control
    373,962 controls
    Type 1 + type 2 diabetes increase hip fracture risk



Table 1:  Studies conducted over the last 15 years linking either type 1 or type 2 diabetes and hip fracture.

Likewise, in an earlier report, Schwartz et al. [9], noted higher fracture rates among older women with type 2 diabetes, and suggested this group might experience more rapid bone loss at the hip with aging than those without the condition, even though their bone mineral density may be increased rather than decreased [10]. In the Asian population where both diabetes and hip fracture rates are rising, Koh et al. [11], found the risk of hip fracture was almost double among people with diabetes compared to those without the disease. This relationship remained even when controlled for by stratifying the data according to body mass index. The relationship was deemed to be strong and dose-dependent based on baseline interviews, and the incidence of hip fractures post-enrollment over a 12 year study period of 63, 257 Chinese adults.

Using a large-population based health care data base, Reyes et al. [12], recently reported that diabetes is independently associated with an increased risk of hip fracture in elderly men. These data were supported by earlier work of Strotmeyer et al. [13]. who found diabetes among older men and women was associated with higher hip fracture rates after adjusting for body mass.

Thus, even though Puar et al. [14]. who produced counter intuitive data stating type 2 diabetes patients with tighter glycemic control are at greater risk of hip fracture, suggesting poor glycemic control is not associated with hip fracture, it seems safe to conclude, adults with either type 1 or type 2 diabetes, may experience a heightened risk for incurring a hip fracture over and above that due to age as concluded by Vestergaard et al. [15]. They may also sustain worse outcomes after hip fracture. However, it appears equally safe to say that this important fact is not always stressed in the context of diabetes management programs or hip fracture prevention programs.

Diabetes and increased risk for poor outcomes after hip fracture: The impact of diabetes among hip fracture cases is quite apparent even if there is sparse literature in the area. Among other detrimental outcomes exacerbated by diabetes, Gulceleik et al. [16], found that patients followed for more than 10 years after sustaining a hip fracture were more likely to die, if they had diabetes type 2 diagnoses. The main factors that were found to influence this were age, and HbA1c levels, suggesting more emphasis on controlling blood sugar among those of higher ages, post hip fracture might be helpful.

Wang et al. [6]. followed a sample of 707 hip fracture patients for one year and found that those hip fracture patients with diabetes had a higher risk of incurring postoperative cardiac complications, urinary tract infections, and gastrointestinal symptoms than healthy controls. They found that before the hip fracture, those with diabetes had more limited functional ability. These diabetes cases, stayed in hospital for longer periods, and underwent longer surgeries than those with no health condition (Table 2). Other data reveal that diabetes raises the risk for shorter life expectancy among hip fracture cases [17], as well as the risk for medical complications after hip fracture surgery [18], as well as second hip fractures [19].

Table 2: Summary of studies depicting selected negative health outcomes of diabetic patients post hip fracture.




  
    Author 
    Sample 
    Results 
    Conclusion 
  
  
    Gulcelik et al. [16] 
    356 hip fractures cases
    1 year survival was almost 20% higher in    controls
    Diabetic patients have increased mortality rates    post hip fracture
  
  
    Huang et al. [58] 
    Secondary analysis of 242, hip fracture    cases 25.2%
    Those with diabetes had higher mortality,    and readmission rates, Those without diabetes had better rates of recovery at    1 year
    Diabetes negatively impacts hip fracture outcomes
  
  
    Janmohammadi et al. [66] 
    195 hip fracture cases
    Diabetics had high intertrochanteric fracture rates. Diabetics required higher blood transfusion volumes
    Awareness and care could reduce poor outcomes
  
  
    Norris et al. [4] 
    477 hip fracture cases, 5489 non diabetics
    Complications increased in those with    diabetes after surgery, Diabetics had longer hospital stays Diabetes cases    had worse baseline functional ability
    Pre and postoperative recovery rates are    influenced by diabetes
  
  
    Wang et al. [6] 
    707 hip fracture cases
    Cases with diabetes had more cardiac and    other complications, post-surgery Initial walking ability of the diabetics    was worse than controls
    Diabetics are at increased risk for post    surgical complications



Table 2:  Summary of studies depicting selected negative health outcomes of diabetic patients post hip fracture.

Factors predisposing to increased hip fracture risk in diabetes cohorts: According to Garg et al. [20], it is the changes in hip geometry that are found among diabetics which predispose to fracture risk in diabetic women. After conducting an observational study of 128 insulin treated type 2 diabetic women, 299 type 2 diabetic women on diet or medication regimens, and 5497 controls, and after adjusting for lean body weight, they found the bone mineral density and bending strength in the femoral neck were significantly reduced when compared to control women.

Yamaguchi and Sugimoto [21] reported that meta-analyses of multiple clinical studies depict increased hip fracture risk and type 2 diabetes cases in the range of 1.4-1.7 compared to controls. They suggested bone quality rather than quantity may be compromised in this group. Another theory is that despite having higher bone density than controls, diabetic women have lower indices of femoral neck strength relative to load, which raises their fracture risk. Guicelik et al. [16], found mortality rates were increased among type 2 diabetes patients after hip fracture, which was partially explained by the presence of elevated HBA1c levels, an indicator of glycemic control. Ishii et al, [22] found that diabetic women have lower femoral neck strength values relative to load, and that insulin resistance appears to play an important role in reducing bone strength in people with diabetes. In addition, research reveals older people with type 2 diabetes, the most common form of diabetes, have a 2.5 fold increased risk of fractures due to their high rate of falling [23,24]. Pipes et al. [25], too found patients with diabetes had an increased risk of recurrent falls. Obesity is also linked to increased falls risk, and is a common feature of diabetes [26]. Napoli et al. [27] found men with diabetes using insulin – which can require the use thiazolidinediones related to increasing the risk of becoming obese and having poor bone density [28] to have an increased risk of non vertebral fractures such as hip fractures, for a given age and bone mineral density. It is possible that those who are overweight incur fractures quite readily due to their altered bone quality [28] as well as the added mechanical impact they sustain in any fall related situation if they are overweight. Their fat mass might also impede their muscular system from serving a shock absorber during perturbations such as falling. Lee et al. [29] found total body muscle mass to be the most significant factor predicting femoral neck bone mineral density and the risk of falls that often lead to hip fractures among elderly cases with type 2 diabetes. Other factors that predict fracture risk in this patient group are alterations in bone material properties leading to increased bone fragility, longer disease duration, inadequate glycemic control, and insulin use [30]. Others are diabetes medications and very tight glycemic control [14]. Poor glycemic control is also a predictor of worse post-surgical outcomes among diabetic hip fracture cases [16]. Other factors are shown in (Box 1).

Keywords	Total Number Publications	Number of Journal Articles
Diabetes	210, 897	181,330
Diabetes and Nutrition	20,253	17,500
Diabetes and Glycemic Control	9358	8958
Diabetes and Exercise	8640	7024
Diabetes and Falls	31	28
Hip Fractures	5836	5338
Fracture Prevention	4881	4423
Hip Fracture Prevention	924	839
Hip Fractures and Diabetes	237	212

Diabetes and Hip Fractures: an Important Underrepresented Topic in the Related Literature

Abstract

Introduction

Methods

Findings

Conclusion

Future Directions

References