Chronic Kidney Disease (CKD)
CVD and CKD share many risk factors, and it appears that inflammation also links periodontitis to the development of kidney disease.22 Pathogens found in oral biofilms have been shown to have the ability to adhere to and invade coronary endothelial cells, leading to atheroma formation and impaired vasculature relaxation. Many researchers postulate that periodontal disease exerts similar effects within the vasculature of the kidney.23
Chronic renal disease is a progressive loss in renal function. Symptoms of diminishing kidney function are nonspecific and may include feeling generally unwell and experiencing a reduced appetite. CKD is identified by a blood test for creatinine. Increased levels of creatinine indicate a falling glomerular filtration rate and a decreased ability of the kidneys to excrete waste products. The most common causes of CKD are diabetes mellitus, hypertension, and glomerulonephritis, which together cause approximately 75% of all adult cases.24
CKD patients are characterized by a few well-established risk factors of periodontal disease. These include poor oral hygiene and diabetes.25 A strong correlation appears to exist between patients on dialysis and the high number of patients suffering from gingivitis (46%) and severe periodontitis (35%).26 Interestingly, the correlation appears to be bi-directional, as patients with CKD have higher prevalence of periodontal disease. Both diseases are associated with chronic low-level inflammation, and periodontitis may lead to endothelial dysfunction, which plays a role in the pathogenesis of kidney disease.27 The negative effects of systemic inflammation on kidney function could occur during active periodontal infection. Inflammation has been reported to be an important predictor of low serum albumin levels among dialysis patients.28
Diabetes is a significant public health problem, affecting 9.3% of the US population (29.1 million patients). It has been estimated that 8.1 million (27.8%) patients with diabetes go undiagnosed.29 The Centers for Disease Control and Prevention reports diabetes diagnoses have increased by more than 3 million in almost 2 years.
Periodontal disease is more common in patients with diabetes. Those with diabetes have twice the risk for periodontal disease of those without the metabolic disorder. In addition, periodontal disease is more prevalent, progresses more rapidly, and is often more severe in patients with type I or type II diabetes.30,31 Periodontal disease is classified as the sixth most common complication of diabetes. Conversely, diabetes is a strong, well-established risk factor for severe periodontal disease.
Patients with periodontal infections have worse glycemic control over time. Grossi reported that in cases of severe periodontal disease, an increase in the severity of diabetes mellitus is reported, and this complicates metabolic control.32 Cytokines secreted because of chronic inflammation are associated with insulin resistance. An infection-mediated cycle of cytokine synthesis and secretion by chronic stimulus from products of biofilm may amplify cytokine response. This helps explain the increase in tissue destruction seen in diabetic periodontitis as well as how periodontal disease may complicate the severity of diabetes.
Treatment of periodontitis appears to improve glycemic control.33 Thus, control of the periodontal infection and associated biofilm should be part of the standard treatment for the diabetic patient.
Periodontal bone loss may progress more rapidly in patients with osteoporosis. Evidence has established a correlation between periodontitis and bone metabolism.34 Early diagnosis of reduced bone mineral density (BMD), even before to the establishment of a significant negative impact on the periodontal tissues, might be important. Smoking and menopausal status were reported not to alter these associations.35
Periodontitis and osteoporosis are two diseases that increase in intensity with age. Findings suggest that periodontal changes can be associated with osteoporosis in postmenopausal women and there is an increase in both conditions as the patient ages.36 Periodontitis is associated with resorption of the alveolar bone and osteoporosis is characterized by bone loss leading to structural bone transformation. Some studies have established a relationship between osteoporosis and periodontitis based on pocket depth and clinical attachment loss.37 However, other investigators have reported that periodontal patients with low BMD may have increased risk of alveolar bone loss based on radiographic analysis but not necessarily attachment level or probing depth.38,39
Medications taken by patients with osteoporosis should be considered before any operative procedures. Intravenous bisphosphonates create a greater risk for the patient than oral bisphosphonates for bone issues and the potential of osteonecrosis of the jaw (ONJ) due to lower vascularity of the jawbone. Sites with increased bone turnover, such as extraction sites or areas of periodontal inflammation, are exposed to higher bisphosphonate doses than the remaining alveolar ridge and may explain greater the susceptibility of such areas to ONJ.40,41
Periodontal biofilm is a reservoir of bacteria and a source of lower airway infections, especially in older patients or those who are debilitated. Bacteria in biofilm can innoculate the respiratory tract when aspirated by the patient. The severity of the oral disease is correlated with the pathogenicity of the bacteria in the oral biofilm. Periodontal pathogens and the presence of cariogenic bacteria are significant risk factors for aspiration pneumonia.
The highest risk patients for respiratory infection (pneumonia and bronchitis) are medically compromised patients with or without respiratory disease who are unable to perform adequate oral homecare. There is strong evidence that elderly patients may be at increased risk of pulmonary issues related to periodontal disease especially as they pass the seventh decade of life, when general health diminishes as well as their ability to render homecare. Evaluation of 328 articles published over an 11-year period reported linking oral hygiene to oral health care–associated pneumonia or respiratory tract infection in elderly people. The authors reported, “There is good evidence that mechanical oral hygiene practices reduce the progression or occurrence of respiratory diseases in high-risk elderly people in nursing homes or hospitals. Mechanical oral hygiene practices may prevent the death of about 1 in 10 elderly residents of nursing homes from health care–associated pneumonia.”42
Meticulous oral homecare is critical in preventing these oral infections by minimizing the potential of aspirating biofilm into the pulmonary system. One author reported, “Oral hygiene intervention significantly reduced occurrence of pneumonia in institutionalized subjects.”43 Additionally, frequent tooth brushing and preoperative use of 0.12% chlorhexidine mouthrinse or gel reduced nosocomial respiratory tract infections.44 Therefore, it may be of general benefit that all elderly patients be placed on chlorhexidine daily rinses as a preventive measure. It has also been demonstrated that use of low concentration peroxides in custom trays has a positive affect on oral biofilms, reducing the bacterial load and decreasing pathogenic material that may be aspirated. This may be a more predictable approach in elderly patients who lack manual dexterity to perform oral homecare with a toothbrush.