Medical conditions and medication use in adults with Down syndrome: A descriptive analysis

Background: We examined the presence of medical conditions and medication use within a sample of adults with Down syndrome. Methods: Retrospective chart review using a sample of 141 adults with Down syndrome and age range of 30 to 65 years. Results: We identify 23 categories of commonly occurring medical conditions and 24 categories of medications used by adults with Down syndrome. Conclusion: Approximately 75 of older adults with Down syndrome in our sample experience memory loss and dementia. Hypothyroidism, seizures, and skin problems also occur commonly. The prevalence of cancer (i.e., solid tumours) and hypertension is extremely low. Older adults with Down syndrome use anticonvulsant more often than younger adults with Down syndrome. The use of multivitamins and medications such as pain relievers, prophylactic antibiotics, and topical ointments is common.

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Kerins, G, Petrovic, K, Bruder, M, and Gruman, C. (2007) Medical conditions and medication use in adults with Down syndrome: A descriptive analysis. Down Syndrome Research and Practice, 12(2), 141-147. doi:10.3104/reports.2009

Adults with intellectual disabilities such as Down syndrome are experiencing simultaneous increases in life expectancy and the prevalence of certain medical conditions [1], including hypothyroidism [2] and sleep apnoea [3]. Premature aging is not uncommon for older adults with Down syndrome [4]. Dementia is common among adults with Down syndrome [5], as dementia and neuropsychological decline may accompany increased life expectancy for adults with Down syndrome. Prevalence data available with regard to dementia in adults with Down syndrome suggest that dementia occurs in 36 - 66% of adults between the ages of 50 to 59 years old and 9 - 11% of adults between the ages of 40 to 49 years old [6,7,8] . Additionally, increases in the use of certain medications are believed to occur among adults with Down syndrome when compared to adults without Down syndrome. Yet, little information has been published with regard to the types of medications and their indications for use.

Numerous medical conditions are believed to be associated with the aging of adults with Down syndrome. Generalised lens opacities such as total cataract [9] may result from increased amounts of free radical reactions in adults with Down syndrome [10]. Hypercholesterolaemia is not uncommon in older adults with Down syndrome [11] and may be associated with family history [12,13]. Hypothyroidism may develop secondary to autoimmune thyroiditis [2]. Obstructive sleep apnoea may result from physiological and anatomical abnormalities in adults with Down syndrome [3]. Adults with Down syndrome experience limitations in cardio-respiratory capacity [14], osteoporosis [15], and late-onset seizures [16]. In fact, late-onset seizures are thought to occur in 75 - 85% of adults with Down syndrome who are affected by Alzheimer's disease after the age of 50 [16].

Adults with Down syndrome are susceptible to the presence of neuropsychological conditions such as anxiety, depression, and dementia. Due to the progressive, age-dependent nature of Alzheimer's disease pathology involving the deposition of diffuse amyloid plaques that accumulate in the brains of adults with Down syndrome who are older than the age of 30[ 5, 17] , adults with Down syndrome are at heightened risk for developing Alzheimer's disease [5, 18] . Research shows that the onset of Alzheimer's disease takes place at approximately 40 years of age [19] , an age which is considered 'young' by many standards in our society. Dementia is difficult to diagnose in adults with Down syndrome who concurrently experience co-morbid states [20]. Further, the rates of co-morbidities are high for adults with Alzheimer's disease [21], thus creating a cycle in which dementia is not readily assessed and the prevention of neuropsychological decline takes on greater complexity.

Purpose of this paper

Based on this information, the need exists for additional research that examines the aging process of adults with Down syndrome. This includes an examination of the presence of medical conditions affecting adults with Down syndrome as well as the medications prescribed for the treatment of these conditions. The purpose of this paper is to investigate the following two questions:

  1. What are the medical conditions that commonly characterise adults with Down syndrome?
  2. What types of medications are commonly used by adults with Down syndrome?

Methods

A retrospective chart review was conducted of 187 adults ages 30 - 65 and with documented intellectual disability. All adults were established patients at a major teaching hospital in a metropolitan area of the United States in which faculty (e.g., certain geriatricians) possessed extensive experience in working with adults with intellectual disabilities. As a result, adults with intellectual disabilities were referred to the hospital from throughout the entire statewide region for geriatric evaluations that included specialised Down Syndrome Mental Status testing and physical assessments.

Approval from the Institutional Review Board of the University School of Medicine was obtained prior to carrying out this study. Data obtained from the chart review were entered into a software spreadsheet created using the Statistical Package for the Social Sciences (SPSS). Identifiers were removed for each chart. No medical record numbers or names of individuals were obtained or entered into the SPSS database.

Within the sample of 187 adults with intellectual disabilities, a total of 141 had a diagnosis of Down syndrome. Based upon the literature, categories of age, physical health conditions, neuropsychological conditions, medications, and demographic variables were created. Categories of age include: (1) up to 39 years old, (2) 40-49 years old, (3) 50-59 years old, (4) and 60 years old or older.

A total of 23 categories of medical conditions were created. They include: anxiety or depression, other mental illness (e.g., psychosis), dementia, arthritis or other musculoskeletal condition, cancer, cardiac condition (murmur), other cardiac condition (e.g., atrioventricular septal defect/AVSD), cataract, diverticulosis/diverticulitis/Crohn's disease, gastroesophageal reflux disease (GERD), Hepatitis B carrier, hydrocephalus, hypercholesterolemia, hypertension, hypothyroidism, osteoporosis, pulmonary conditions (e.g., asthma, chronic obstructive pulmonary disease, pneumonia), seizure disorder, skin conditions, (obstructive) sleep apnoea, stool incontinence and urinary incontinence. Likewise, a separate category entitled "diagnosed disability of any type" (e.g., physical, emotional, learning) was developed, as we believe that this category is distinctive and differs conceptually from medical or neuropsychological conditions.

Less than 50 years old

50 years old or older

Total

number

%

number

%

number

%

Gender of individual: Male

52 67 32 50 84 59

Gender of individual: Female

25 33 32 50 57 41

Total

77 100 64 100 141 100

Table 1 | Gender and age of individual with Down syndrome

A total of 24 categories of medications were created and reflect prescribed medications only. The categories of medications are: anti-anxiety medications, anticonvulsants, antidepressants, anti-hypertension medications, antipsychotic medications, antispasmodics, cholesterol-lowering medications, cholinesterase inhibitors, Fosamax - or alendronate sodium, a biphosphonate that inhibits bone resorption without impeding mineralisation [22], GERD-related medications (e.g., proton pump inhibitors), hormones (other than thyroid-related hormones), hypothyroid-related medications, respiratory medications (e.g., metered dose inhalers/MDIs), Vitamin A, Vitamin B12, Vitamin C, Vitamin E, calcium, folic acid, iron, multivitamin, no vitamin/mineral, other vitamin/mineral, and other medications (e.g., pain relievers, prophylactic antibiotics, and topical ointments).

Results

We examined the presence of medical diagnoses and medication utilisation as they pertain to adults with Down syndrome. Cross-tabulations were performed for all categories of medical conditions and medications. The number of medications used by adults with Down syndrome ranged from 0 - 16 medications per adult.

The data contain multiple cohorts of adults. However, we specifically focused on: (1) adults with Down syndrome (n = 141), and (2) adults without Down syndrome (n = 45). The group of adults with Down syndrome was divided into (1) adults under the age of 50 years, known as 'younger adults' (n = 77) and (2) adults 50 years old or older, known as 'older adults' (n = 64). The average age of this sample was approximately 51 years old (50.98 years), with a range of 31-65 years. The sample contained greater numbers of men (n = 84) as compared to women (n = 57). Fewer men were found in the 50+ group (n = 32) than in the group of adults under the age of 50 (n = 52). More women were found in the 50+ group (n = 32) as compared to those under the age of 50 years (n = 25). (See Table 1.)

Less than 50 years old 50 years old or older Total
number % number % number %
Anxiety or depression
Anxiety 4 5 6 9 10 7
Depression 17 22 8 13 25 18
Both 5 7 0 0 5 7
Neither 51 66 50 78 101 72
Total 77 100 64 100 141 104
Other mental illness
Yes 14 18 10 16 24 17
No 63 82 54 84 117 83
Total 78 100 64 100 141 100
Dementia
Yes 55 71 52 81 107 75
No 23 30 12 19 35 25
Total 78 100 64 100 142 100
Arthritis
Yes 6 8 12 19 18 13
No 71 92 52 81 123 87
Total 77 100 64 100 141 100
Cancer
Yes 2 3 1 2 3 2
No 75 97 63 98 138 98
Total 77 100 64 100 141 100
Cardiac condition: Murmur
Yes 10 13 10 16 20 14
No 67 87 54 84 121 86
Total 77 100 64 100 141 100
Cardiac condition: other
Yes 14 18 12 19 26 18
No 63 82 52 81 115 82
Total 77 100 64 100 141 100
Cataract
Yes 10 18 9 14 19 14
No 67 84 55 86 122 87
Total 77 100 64 100 141 101
Diagnosed disability of any type
Yes 12 16 11 17 23 16
No 65 84 53 83 118 84
Total 77 100 64 100 141 100
Diverticulosis/Diverticulitis/Crohn's disease
Yes 3 4 5 8 8 6
No 74 96 59 92 133 94
Total 77 100 64 100 141 100
Gastroesophageal reflux disorder (GERD)
Yes 11 15 9 15 20 14
No 66 85 56 85 121 86
Total 77 100 64 100 141 100
Hepatitis B carrier
Yes 4 5 8 13 12 9
No 73 95 56 88 129 92
Total 77 100 64 101 141 101
Hydrocephalus
Yes 0 0 2 3 2 1
No 77 100 62 97 139 99
Total 77 100 64 100 141 100
Hypercholesterolaemia
Yes 6 8 6 9 12 9
No 71 92 58 91 129 92
Total 77 100 64 100 141 101
Hypertension
Yes 2 3 2 3 4 3
No 75 97 62 97 137 97
Total 77 100 64 100 141 100
Hypothyroidism
Yes 30 39 27 42 57 40
No 47 61 47 58 84 60
Total 77 100 64 100 141 100
Osteoporosis
Yes 20 26 14 22 34 24
No 57 74 50 78 107 76
Total 77 100 64 100 141 100
Pulmonary condition
Yes 13 17 13 20 26 18
No 64 83 51 80 115 82
Total 77 100 64 100 141 100
Seizure disorder
Yes 8 10 22 34 30 21
No 69 90 42 66 111 79
Total 77 100 64 100 141 100
Skin condition
Yes 15 19 22 34 37 26
No 62 81 42 66 104 74
Total 77 100 64 100 141 100
Sleep apnoea
Yes 16 21 11 17 27 19
No 61 79 53 83 114 81
Total 77 100 64 100 141 100
Stool incontinence
Yes 4 5 3 5 7 5
No 73 95 61 95 134 95
Total 77 100 64 100 141 100
Urinary incontinence
Yes 14 18 11 17 25 18
No 63 82 53 83 116 82
Total 77 100 64 100 141 100

Table 2 | Medical condition and age of individual with Down syndrome

Table 2 contains information pertaining to medical conditions by age group. Regarding the entire sample of adults with Down syndrome, relatively large percentages of dementia (75.9%), hypothyroidism (40.4%), skin conditions (26.2%), seizure disorder (21.3%), and pulmonary conditions (18.4%) exist. Relatively small percentages of hydrocephalus (1.4%) and hypertension (2.8%) exist for this sample of adults with Down syndrome. In both groups, the presence of certain cardiac conditions (e.g., AVSD) and GERD exist in nearly equal percentages (18.4% and 14.2%, respectively). Overall, older adults (50+ years old) with Down syndrome experience more instances of all medical conditions except depression, other mental illnesses, cancer, osteoporosis, sleep apnoea, and stool and urinary incontinence as compared to the younger group of adults (>50 years old) with Down syndrome.

Anxiety is present for 9.4% of older adults with Down syndrome, and dementia occurs in over 80% of cases in this group. Adults with Down syndrome who are 50 years old or older are found to have higher percentages of arthritis/other musculoskeletal conditions (19%), heart murmurs (16%), and cataracts (14%) when compared to the younger group. Greater percentages of older adults with Down syndrome experience diverticulosis or a related condition (8%), are carriers of the Hepatitis B virus (13%), and have higher cholesterol levels (9%) as compared to the younger group of adults with Down syndrome. Over 40% of older adults with Down syndrome experience hypothyroidism, and nearly 35% have been diagnosed with seizure disorder or skin conditions.

Table 3 represents medication use according to the age of adults with Down syndrome. Comparable percentages of younger adults and older adults with Down syndrome use anti-anxiety medications (16% vs. 16%), cholesterol-lowering agents (9% vs. 11%), hormones other than thyroid-related hormones (13.0% vs. 14%), and calcium (30% vs. 30%). Less than 10% of this sample of adults with Down syndrome uses folic acid, iron, vitamin A, vitamin B12, or vitamin C while more than 50% use vitamin E. Less than 10% of the entire sample of adults with Down syndrome uses cholinesterase inhibitors. Comparable percentages of younger and older adults with Down syndrome use Fosamax (21% vs. 23%) and medications for gastroesophageal reflux disease (18% vs. 22%), hypothyroidism (35% vs. 38%) and respiratory conditions (26% vs. 28%).

Less than 50 years old 50 years old or older Total
number % number % number %
Anti-anxiety medications
Yes 12 16 10 16 22 16
No 65 84 54 84 119 84
Total 77 100 64 100 141 100
Anticonvulsants
Yes 12 16 24 38 36 26
No 65 84 40 62 105 75
Total 77 100 64 100 141 100
Antidepressants
Yes 19 25 9 14 28 20
No 58 75 55 86 113 80
Total 77 100 64 100 141 100
Anti-hypertension medications
Yes 3 4 12 19 15 11
No 74 96 52 81 126 89
Total 77 100 64 100 141 100
Antipsychotic medications
Yes 7 9 12 19 19 14
No 70 91 52 81 122 87
Total 77 100 64 100 141 101
Antispasmodics
Yes 1 1 3 5 4 3
No 76 99 61 95 137 97
Total 77 100 64 100 141 100
Cholesterol-lowering agents
Yes 7 9 7 11 14 10
No 70 91 57 89 127 90
Total 77 100 64 100 141 100
Cholinesterase inhibitors
Yes 9 12 5 8 14 10
No 68 88 59 92 127 90
Total 77 100 64 100 141 100
Fosamax
Yes 16 21 15 23 31 22
No 61 79 49 77 110 78
Total 77 100 64 101 141 100
GERD-related medications
Yes 14 18 14 22 28 20
No 63 82 50 78 113 80
Total 77 100 64 100 141 100
Hormones
Yes 10 13 9 14 19 14
No 67 87 55 86 55 87
Total 77 100 64 100 141 101
Hypothyroid-related medications
Yes 27 35 24 38 51 36
No 50 65 40 63 90 64
Total 77 100 64 101 141 100
Respiratory medications
Yes 20 26 18 28 38 27
No 57 74 46 72 103 73
Total 77 100 64 100 141 100
Vitamin/Mineral: Vitamin A
Yes 1 1 0 0 1 1
No 76 99 64 100 140 99
Total 77 100 64 100 141 100
Vitamin/Mineral: Vitamin B12
Yes 2 3 5 8 7 5
No 75 97 59 92 134 95
Total 77 100 64 100 141 100
Vitamin/Mineral: Vitamin C
Yes 3 4 4 6 7 5
No 74 96 60 94 134 95
Total 77 100 64 100 141 100
Vitamin/Mineral: Vitamin E
Yes 39 51 35 55 74 53
No 38 49 29 45 67 48
Total 77 100 64 100 141 101
Vitamin/Mineral: Calcium
Yes 23 30 19 30 42 30
No 54 70 45 70 99 70
Total 77 100 64 100 141 100
Vitamin/Mineral: Folic Acid
Yes 1 1 3 5 4 3
No 76 99 61 95 137 97
Total 77 100 64 100 141 100
Vitamin/Mineral: Iron
Yes 3 1 0 0 1 1
No 97 99 64 100 140 99
Total 100 100 64 100 141 100
Vitamin/Mineral: Multivitamin
Yes 23 30 24 38 47 33
No 54 70 40 63 94 67
Total 77 100 64 101 141 100
Vitamin/Mineral: None
Yes 24 31 18 28 42 30
No 53 69 46 72 99 70
Total 77 100 64 100 141 100
Vitamin/Mineral: Other
Yes 0 0 1 2 1 1
No 77 100 63 98 140 99
Total 77 100 64 100 141 100
Other Medication(s)
Yes 26 34 30 47 56 40
No 51 66 34 53 85 60
Total 77 100 64 100 141 100

Table 3 | Medication use and age of individual with Down syndrome

Extremely low percentages of younger and older adults with Down syndrome use antispasmodic medications (1% vs. 5%). Considerably low percentages of younger adults with Down syndrome use anti-hypertension medications (4%) as compared to older adults (19%). Likewise, lower percentages of younger adults than older adults with Down syndrome use anticonvulsants (16% vs. 38%) and antipsychotic medications (9% vs. 19%); however, greater percentages of younger adults with Down syndrome use antidepressants as compared to older adults with Down syndrome (25% vs. 14%). Greater percentages of older adults with Down syndrome use multivitamins as compared to younger adults with Down syndrome (38% vs. 30%). Finally, other medications such as pain relievers, prophylactic antibiotics, and topical ointments are used more often by older adults with Down syndrome as compared to younger adults with Down syndrome (47% vs. 34%).

Discussion

Overall, our study involved 141 adults with Down syndrome. Our sample of adults with Down syndrome was approximately 60% male and 40% female. Slightly more than 75% of our sample experienced memory loss (as reported by family members or caregivers) and/or were diagnosed with dementia. This is not surprising, given that one of the primary reasons for the referral of adults with Down syndrome to the physician clinics at this metropolitan hospital setting occurs as a result of signs and symptoms of dementia in the adult patient. Nonetheless, adults with Down syndrome who are 50 years old or older constitute a greater percentage (81%) of those with dementia as compared to younger adults (71%). These findings are consistent with research demonstrating that memory loss and the likelihood of dementia increase with age for adults with Down syndrome.

Our study demonstrates that slightly more than 20% of adults with Down syndrome experience seizures, with greater percentages of older adults with Down syndrome diagnosed with seizure disorder (34%) as compared to the younger group (10%). Although the occurrence of seizures in adults with Down syndrome has been recognised for years, our data analysis suggests that (new onset) seizures may accompany the aging process.

While cardiac conditions such as murmurs (14%) and ASVD (18%) occur in this sample of adults with Down syndrome, extremely low percentages of hypertension (3%) and hypercholesterolaemia (9%) are found. In fact, coronary artery disease does not appear to occur in this sample of adults with Down syndrome. Further, due to the fact that very few adults with Down syndrome in this sample were diagnosed with diabetes mellitus, we do not have a category for the presence of diabetes mellitus. However, given the implications that diabetes mellitus has for the development of coronary artery disease, we are interested in future research that examines the individual and combined effects of diabetes mellitus, HTN, and hypercholesterolaemia on the development of coronary artery disease in adults with Down syndrome.

Relatively large percentages of older adults with Down syndrome (34%) experience skin conditions such as fungal infections, psoriasis, and skin rash as compared to younger adults with Down syndrome (20%), leading us to question whether the presence of such skin conditions is related to environment, the onset of memory loss and dementia, and poor self-care that may occur over time. Additionally, urinary incontinence is present in nearly 18% of this sample and may be related to the high percentage of skin conditions in this sample of adults with Down syndrome.

Hypothyroidism is present in over 40% of this sample of adults with Down syndrome, a finding that is consistent with prior research demonstrating the commonality with which this medical condition occurs in adults with Down syndrome. Osteoporosis occurs in about 24% of the overall sample of adults with Down syndrome. Interestingly enough, however, osteoporosis occurs more frequently in younger adults with Down syndrome (26%) as compared to the older group (22%). Other medical conditions that commonly occur in this sample of adults with Down syndrome include gastroesophageal reflux disease (14%), pulmonary conditions (18%), and obstructive sleep apnoea (19%). Geriatricians, geriatric nurses, and other members of the health care team should be aware of the occurrence of medical conditions such as these, so as to focus assessment and treatment options as well as improve the overall quality of life for adults with Down syndrome.

Our review of medication use in this sample of adults with Down syndrome confirms the presence of thyroid supplementation, anti-anxiety and antidepressant medications, and anticonvulsants as common and appropriate. Multivitamins are used at least a third of the time, and Vitamin E is used by over 50% of adults in this sample. We are encouraged by the use of calcium with Vitamin D (30%) and Fosamax (22%) to help in maintaining bone health, thereby decreasing the risk of osteoporosis in this vulnerable group of adults.

A relationship exists between medical conditions and medications occurring in this sample of adults with Down syndrome. Overall, the majority of medications are used to treat commonly occurring medical conditions, with the exception of memory loss and dementia. Relatively little use of cholinesterase inhibitors (10%) occurs in this sample of adults with Down syndrome; only 12% of younger adults with Down syndrome and 8% of older adults with Down syndrome use cholinesterase inhibitors. We believe that this can be explained by the fact that the use of cholinesterase inhibitors to slow the progression of memory loss in adults with Down syndrome has yet to be examined and understood more fully.

Further research is necessary in order to assess the natural history of commonly occurring medical conditions such as those included in our study. The fact that certain medical conditions such as cancer and hypertension appear to occur infrequently in adults with Down syndrome warrants further study; this is particularly the case when comparing samples such as these to the general population. This sort of study may include comparisons of men and women with regard to incidence and prevalence of medical conditions. Barriers to health care services and appropriate diagnosing and treatment options for adults with Down syndrome should be examined. Finally, systems of care that allow for screening and prevention of commonly occurring medical conditions such as these must be developed and implemented.

Limitations

Our study is primarily limited methodologically with regard to the cross-sectional nature of our research design and our sampling strategy. A longitudinal design that would permit the researchers to follow participants over time is ideal, particularly when considering research that applies to the aging process. The onset of certain, commonly occurring medical conditions (e.g., memory loss and dementia, hypothyroidism, seizure disorder) could be pinpointed, thereby facilitating a more thorough understanding of appropriate intervention, treatment, and cure. Further, our study is not powered for inferential statistical tests that have the potential to demonstrate significance.In our sample of adults with Down syndrome, the point at which an adult in the "<50 years old" group develops dementia, hypothyroidism, or seizure disorder, for instance, is no clearer than for adults in the "50+" group. We have no data pertaining to family history of hypercholesterolaemia, even though the presence of this condition may be familial to a certain extent. Likewise, we are limited in our sampling design in that we are dependent upon a convenience sample of adults with Down syndrome. This creates difficulty with representation and the comparison of our sample to the larger population of adults with Down syndrome. As a result, the ability to generalise the findings of our study is present but hindered. Overall, we believe that a study such as this that identifies commonly occurring medical conditions and medications that characterise adults with Down syndrome is a beginning step to future research that more definitively addresses the aging process for adults with Down syndrome.

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doi:10.3104/reports.2009

Gerard Kerins, Kimberly Petrovic, Mary Beth Bruder and Cynthia Gruman are at the University of Connecticut Health Center, USA.

© 2007 The Authors. Journal Compilation © 2007 The Down Syndrome Educational Trust.

Received: 1 November 2006; Accepted 14 February 2007; Published online: 06 November 2007.