Incidence and mortality trends of aspiration pneumonia in Parkinson, 1979-2010.
Akbar U, Dham B, He Y, Hack N, Wu S, Troche M, Tighe P, Nelson E, Friedman JH, Okun MS. Incidence and mortality trends of aspiration pneumonia in Parkinson, 1979-2010. , Parkinsonism Relat Disord. 2015 Sep; 21(9):1082-6. doi: 10.1016/j.parkreldis.2015.06.020. Epub 2015 Jul 2.
Introduction: Parkinson’s disease (PD) is typically known for tremulousness, bradykinesia, and gait disturbance. However, other motor symptoms, such as swallowing difficulties, are common for people with PD (PWP). Swallowing difficulties can lead to aspiration pneumonia which can cause death. Aspiration pneumonia is a condition caused when an individual breathes in instead of swallows food, saliva, liquids, or other foreign materials that cause a bacterial infection in one’s lungs. A 1999 longitudinal study found that aspiration pneumonia was the leading cause of death for PWP followed by cardiovascular issues, cancer, and stroke. Due to improved medicinal and surgical treatment of PD survival rates of PWP have increased by about 5 years. The authors of this study suggested that although the rates of aspiration pneumonia likely will increase in the PD population due to PWP living longer it is hoped that due to increased awareness of the condition and improved medical services since 1999 that the mortality rates will not. The authors sought to additionally evaluate the incidence and mortality rates of aspiration pneumonia by looking at a national database of such data from 1979-2010.
Methods: The authors divided the PWP data into five age groups spanning a decade each, starting at age 50 through 90+. There was also a control group of people that did not have PD. Multiple analyses were conducted across the 32 year span as well as within each decade but due to changes in medications and surgical interventions they also looked at a subset of the data over the last five years.
Incidence: Those more likely to have aspiration pneumonia were older men (mean age = 77) with PD. Over the 32 year span there was a large increase of the number of cases of aspiration pneumonia that required hospitalization those with and without PD. They also found that as time went on the age of the patients requiring hospitalization increased (e.g. 74 years old vs. 82). Looking at the gender differences it was noted that men with PD were 2 times more likely to develop aspiration pneumonia than women. Similar findings were observed only looking at the last five year subset as well.
Mortality: Notably, PWP had less mortality during hospitalization for aspiration pneumonia than those without PD. Both groups had a reduction in mortality across time PD from 30% (1979-1985) to 14% (2006-2010) and non-PD, 36-17%. Again a gender effect was found that men with PD were more likely to die from the pneumonia while hospitalized than women. Interestingly the age range with the highest mortality was the 50-60 year olds with PD over the three decades. However, in looking at the last five year subset the reduced mortality information generally did not change with the exception that the mortality increased as the PWP got older and was not specific to the 50-60 year old group as found above.
Conclusion: As hypothesized the authors found that the incidence of aspiration pneumonia is greater for PWP (3.8x) than those without PD and has increased across the last three decades but the mortality has decreased significantly by about 30%. As PWP aged the incidence of aspiration pneumonia also increased. Notably the mortality in PWP from aspiration pneumonia was greatly reduced from prior studies and was less than those who don’t have PD. This finding is likely due to increased awareness of swallowing difficulties in PWP and possibly earlier detection and initiation of treatment. Both groups also had a reduction in mortality likely due to improved medical care, better antibiotics, and increased awareness of aspiration pneumonia as medical care typically improves with time. There were multiple limitations of this study which were clearly addressed in the article but as the authors discussed it is very important to look at large epidemiological estimates of disease information to improve detection, treatment, long term care options, and patient survival.