Risk Behaviors and Spectrum of Diseases Among Elderly Travelers: A Comparison of Younger and Older Adults

Authors


Danny Alon, MD, Traveler's Clinic and Infectious Diseases Unit, Meir Medical Center, 59 Tchernichovski St., Kfar Saba 44281, Israel. E-mail: danny.alon@clalit.org.il

Abstract

Background. Elderly travel to the developing world is increasing. Little information is available regarding risk behaviors and health during and after travel in this population.

Methods. We compared the risk factors and occurrence of travel-related diseases in two populations of Israelis, travelers aged 60 years and older and travelers in the age group of 20 to 30 years. Only people traveling for less than a month were included. Pre-travel, each person received routine counseling regarding travel-associated health risks, was immunized, and given anti-malarial prescriptions as needed.

Travelers were surveyed by telephone 6 to 12 months following travel about underlying medical conditions, current medications, and travel history. Risk and preventive behaviors, compliance with anti-malarial prophylaxis, and history of illness during and after travel were assessed.

Results. Of patients who visited the clinic from January to June 2008, 191/208 (91%) travelers aged 60 and older and 203/291 (69%) travelers aged 20 to 30 years were contacted by phone and recruited. Fewer elderly travelers drank open drinks, compared to young travelers (8% vs 35%, p < 0.01), and fewer purchased street food compared to young travelers (16.2% vs 37.9%, p < 0.01). More elderly travelers were fully compliant with their anti-malarial chemoprophylaxis regimen (60.7% vs 33.8%, p < 0.01). More elderly travelers took organized tours (61% vs 2%, p < 0.001). Young travelers more often backpacked (50.7% vs 10.4%, p < 0.001). Illness, most commonly diarrhea, was reported by 18.8% of elderly travelers compared to 34.0% of the young travelers (p = 0.001). In a logistic regression model only travel to East Asia (OR 4.66) (95%CI 1.93–11.22) and traveling under basic conditions (OR 1.94) (95% CI 1.42–3.29) remained significantly associated with illness, irrespective of age.

Conclusions. Because elderly travelers tend to comply with health-related recommendations better and use less risky travel modes, their risk for illness during travel was lower. Traveling to East Asia and travel mode are associated with illness during travel, irrespective of age.

In recent years, travel to the developing world has become increasingly popular among the elderly. Travelers over 55 years of age currently make up 15% of Thailand's backpackers compared to only a few years ago.1 Two surveys from US pre-travel clinics reported that the proportion of travelers 65 years and older was 14% at one site,2 whereas at the other site one third of the travelers were older than 60 years and 1.5% were older than 80 years.3

Advanced age is an important consideration in pre-travel consultations owing to several factors. Increasing age is associated with physiologic changes as well as with an increased probability of underlying medical conditions and prescription medications.4–6 Age has also been associated with decreasing immune responses to standard pre-travel vaccinations and thus elderly travelers might be more susceptible to vaccine-preventable diseases.7 However, very little information is available regarding the risk behaviors and the health of elderly travelers, before, during, and after travel, compared to their younger counterparts. Due to their more complex medical background and decreasing immunity we hypothesized that elderly travelers would be more prone to various health risks and would seek medical care more intensively during and after travel.

The objective of this study was to assess the risk factors for travel-related diseases and their occurrence in a population of elderly (aged 60 years and older) Israelis traveling to developing countries compared to young Israeli travelers (aged 20–30 years).

Methods

Our travel clinic boasts about 6,500 visits per year and is open to travelers of all ages. Travel clinic visits are covered by all health insurances; thus, attending the clinic requires a modest self-payment only.

Inclusion criteria were individuals aged 20 to 30 years or 60 years and older who attended the Meir Medical Center Traveler's Clinic from January to June 2008. Since the majority of the elderly travel for less than a month, to avoid heterogeneity, only people traveling within this time frame were included.

Prior to travel, each person received detailed counseling and written information regarding travel-associated health risks, including malaria, traveler's diarrhea, and mountain sickness according to professional guidelines.8 Counseling to all travelers was performed by a staff of three infectious diseases physicians, and included a filmed presentation followed by personal counseling done according to a standardized form. All travelers were immunized against vaccine-preventable illnesses according to current recommendations8 and provided with prescriptions for prophylactic anti-malarial medications as needed according to their itinerary.

Six to 12 months after the pre-travel clinic visit (4 to 10 months after return), all travelers fitting the inclusion criteria were systematically approached by telephone. A maximum of four attempts were made, at different times of the day, to contact each traveler. Travelers who had been contacted were enrolled and interviewed by telephone using a standardized questionnaire. The questionnaire addressed demographics, underlying medical conditions, current prescription medications, travel history, and characteristics. Risk behaviors, preventive measures, and compliance with anti-malarial medications were assessed. Risk behaviors assessed included eating and drinking habits (purchasing food from street vendors, eating food that was not properly cooked, drinking tap water, open beverages or using ice) as well as non-compliance with malaria prophylaxis measures (using repellants and chemoprophylaxis) and mountain travel. Having bought food on the street, eating improperly cooked food, or drinking anything apart from canned/bottled beverages even once were considered risky behaviors. Not taking chemoprophylaxis in full, according to the instructions given in the pre-travel consultation, was considered non-compliance. We collected information concerning fever, diarrhea, respiratory symptoms, rashes, accidents, and bites, as well as the need for medical care and its nature during travel and up to 1 month afterwards.

The study was approved by the Meir Medical Center Institutional Review Board. Differences in variables between age groups and between being ill or not were calculated using the Chi-square test for nominal variables and the t-test for continuous variables. Logistic regression was used to identify variables explaining illness during travel or within a month after returning home. Statistical significance was set at p < 0.05. Statistical analysis was done using spss-15 software.

Results

Study Population

From January to June 2008, 208 travelers aged ≥60 years and 291 travelers aged 20 to 30 years all of whom planned to travel for less than 30 days attended the Traveler's Clinic. All were approached by phone. Of these, 191 (91%) and 203 (69%), respectively, were available and recruited for participation in the study. All agreed to take part except for one elderly traveler. Patient and travel demographics are described in Table 1.

Table 1.  Characteristics of the study population and travel demographics
Characteristic≥60 age group20–30 age groupp value
Travelers studied191203 
Average age65.60 ± 5.224.8 ± 2.7 
Sex   
 Male103(53.9%)99(48.7%) 
 Female88(46.1%)104(51.3%) 
Destination  p < 0.001
 South America58(30.3%)16(7.8%) 
 Central America4(2%)14(6.8%) 
 Africa28(14.6%)14(6.8%) 
 East Asia101(53.1%)159(78.6%) 
Duration of travel (d)19.9 ± 6.326.2 ± 6.3 
Travel mode  p < 0.001
 Hotel vacation51(26.7%)82(40.3%) 
 Business3(1.5%)15(7.3%) 
 Backpacking20(10.4%)103(50.7%) 
 Organized tour117(61.4%)3(1.7%) 
Underlying medical73(38.2%)5(2.4%)p < 0.001
 condition   
Mountain travel50(26.1%)24(11.8%)p < 0.01
Acetazoleamide use29(58%)2(8.3%)p < 0.01

The mean age of the elderly travelers was 65.6 ± 5.2 years (range 60–82) while the mean age of the young travelers was 24.8 ± 2.7 years. Sex distribution in the two groups was similar. Underlying medical conditions were by far more common in the elderly group of travelers (38% vs 2%, p < 0.001). Hypertension was the most common (33 travelers), followed by hyperlipidemia (21), cardiovascular disorders (18), past or present malignancy (11), diabetes (7), and asthma (2). Past medical history in the young age group included asthma (4 travelers), anemia (1), and diabetes (1).

The most popular destinations among the elderly travelers were East Asia (53%, mostly India) and South America (30%), while among the young age group East Asia was the most popular destination (79%, mostly Thailand). Significantly more elderly travelers went to South America and India than young travelers, while significantly more young travelers visited Thailand (p < 0.001).

As for travel purpose and accommodation, significantly more elderly travelers opted for organized tours (61% vs 2%, p < 0.001). Young travelers more often backpacked (50.7% vs 10.4%, p < 0.001). Hotel vacations and business trips were also more common among the young travelers.

Risk Behaviors

Eating and Drinking Habits

Eating and drinking habits differed significantly between the study groups. Only 15 (8%) elderly travelers drank tap water or open drinks, compared to 71 (35%) of the young travelers (p < 0.01). Eating habits also differed significantly between the age groups: 31 (16.2%) elderly travelers purchased food from street vendors, while 77 (37.9%) young travelers ate food bought on the street (p < 0.01).

Anti-Malarial Chemoprophylaxis

In accordance with the different travel destinations, more of the elderly travelers were prescribed anti-malarials. Atovaquone/proguanil was recommended for the majority of elderly travelers, while mefloquine was recommended for the majority of the young travelers (Table 2). Four elderly travelers reported side effects, mostly gastrointestinal and mild; two were taking mefloquine and two atovaquone/proguanil. Three young travelers had similar side effects, all taking mefloquine. Significantly more elderly travelers were fully compliant with their chemoprophylaxis regimen (60.7% vs 33.8%, p < 0.01). Significantly fewer elderly travelers stated that they had “heard of possible side effects” (7.1% vs 29%, p = 0.05) as a reason for not complying with their recommended regimen. Other stated reasons were “nobody takes these drugs anyway” (19.6% and 25.8% elderly vs young, respectively), “not believing in treatment effectiveness” (6.2% and 1.6%), and “inconvenient regimen” (2.6% and 8%). Significantly fewer elderly travelers used mosquito repellent (Table 2).

Table 2.  Malaria chemoprophylaxis
 ≥60 age group(n = 191)20–30 age group(n = 203)p value
Anti-malarial prescribed112(58.6%)62(30.4%)NS
Mefloquine35(31.2%)31(50%)NS
Atovaquone/proguanil75(66.9%)23(37%)NS
Chloroquine2(1.7%)8(13%)NS
Compliance with anti-malarials68(60.7%)21(33.8%)<0.01
Use of repellents89(46.6%)123(60%)0.005

Mountain Travel

Significantly more of the elderly travelers reached heights above 1,500 m during their travel (26.1%) compared to their young counterparts (11.8%, p < 0.01). Significantly more elderly travelers who had reached these heights used acetazoleamide for mountain sickness prevention (58% vs 8.3%, p < 0.01).

Illness During or Following Travel

Reported Illness

Illness was reported by 36 (18.8%) elderly travelers compared to 69 (34.0%) young travelers (p = 0.001; Table 3). The most common illness was diarrhea, reported by 19 (9.9%) of the elderly travelers and 50 (24.6%) of the young travelers (p < 0.01). Furthermore, the mean duration of diarrhea was significantly shorter in the elderly travelers' group 2.7 ± 1.8 days, range 1 to 7 days, vs 5.1 ± 3.6 days, range 1 to 30 days in the younger group (p < 0.01). Respiratory tract symptoms were the next most common health problem, reported by about 5% of both groups. Elderly travelers reported significantly fewer febrile episodes, usually in association with a defined illness, such as diarrhea or respiratory tract infection. Skin disorders were reported by 2% of the travelers in both groups.

Table 3.  Reported illness during and within 30 days after travel
Illness reported≥60 age group (n = 191)20–30 age group (n = 203)p value
Illness during travel   
 Any36(18.8%)69(34%)0.001
 Diarrhea19(9.9%)50(25%)<0.01
 Duration of diarrhea2.7 ± 1.8 days5.1 ± 3.6 days<0.01
 Fever6(3.1%)17(8.47%)0.027
 Respiratory tract symptoms9(4.7%)12(5.9%)NS
 Skin disorders4(2.1%)5(2.5%)NS
 Headache, dizziness2(1.0%)0NS
 Accidents/Injuries2(1.0%)0NS
Illness following travel   
 Any13(6.8%)11(5.4%)NS
 Diarrhea1(0.52%)7(3.44%)0.04
 Respiratory tract symptoms5(2.6%)4(1.97%)NS
 Severe jetlag4(2.09%)0NS
 STD1(0.52%)0NS
 Others2(1.04%)0NS

Two elderly travelers and none of the young travelers reported headache and dizziness, unrelated to height. Two elderly travelers and none of the young travelers sustained accidents, both traumas were secondary to falls. There were no reports of chest pain, animal bites, mountain sickness, or motion sickness in either group.

Illness after returning home was reported by about 5% of the travelers in both groups. Data concerning illness after return are presented in Table 3. While most (7) of the young travelers sick on return had diarrheal diseases, only one elderly traveler had diarrhea during the first 30 days after returning home (p = 0.04). One elderly traveler underwent surgery for repair of a fracture sustained during his journey and another was newly diagnosed with diabetes. There were no statistically significant differences between the groups regarding post-travel illnesses.

Risk Factors for Illness

Univariate Analysis. Travelers who reported an illness were younger (p = 0.001) and were more often backpackers (p = 0.002). Visiting East Asia in general (excluding Thailand) and Thailand in particular were significantly associated with an illness (p = 0.001 and p = 0.014, respectively). Travel to India did not confer an increased risk (p = 0.35). Travel for business or being on an organized tour seemed to have a protective effect that did not reach statistical significance (p = 0.095 and p = 0.084, respectively). No association was found between foods and drink hygiene and illness (p = 0.84 and p = 0.74, respectively).

Multivariate Analysis. The risk factors that were found significant for illness in the univariate analysis, age, visiting East Asia, visiting Thailand, and type of travel, were further analyzed in a logistic regression model. Travel to East Asia [OR 4.66 (95% CI 1.93–11.22)] and traveling under basic conditions as a backpacker [OR 1.94 (95% CI 1.42–3.29)] remained significantly associated with illness.

Medical Care

Eight (4.2%) elderly travelers and 10 (4.9%) young travelers report seeking medical care due to illness during their trip. The most common reason for obtaining care was gastrointestinal illness. Only two travelers, both in the young age group, one who visited Tanzania and the other Bolivia, were hospitalized. The first traveler was diagnosed with typhoid fever and the other was admitted because of fever and diarrhea. Many travelers who reported an illness chose to self-medicate, including 19 (52.8%) elderly travelers and 24 (34.8%) young travelers, using frequently over-the-counter symptomatic drugs. These drugs included mostly decongestants (such as pseudoephedrine), antipyretics (such as paracetamol), analgesics (such as ibuprofen), and anti-diarrheal medications (such as loperamide). Only six (25%) travelers in the young age group and one (5.3%) elderly traveler self-treated with antibiotics.

Discussion

In this study, we compared the characteristics of an elderly and a young population traveling to developing countries. Although elderly travelers had a greater number of chronic diseases, they reported illnesses significantly less frequently. Elderly travelers tended to comply better with dietary restrictions and malaria chemoprophylaxis. In a multivariate analysis, after controlling for age, medical background, travel duration and destination, travel style and risk behaviors, only visiting East Asia and backpacking remained significantly associated with illness during travel, regardless of age group.

Adherence to traditionally recommended dietary restrictions was generally high in both age groups. The elderly group had an even greater adherence; only 8% drank open beverages compared to 35% of younger travelers, while only 16% purchased foods from street vendors compared to 38% of younger travelers. This compliance with food and drink hygiene is higher than the 20% to 50% reported in other studies.9,10 We assume that the travelers studied here, ie, those who visited a travel clinic, were more aware and concerned and therefore more willing to implement the recommended precautions, compared to the general population of travelers.

Illness was reported by 19% of elderly travelers, compared to 34% of young travelers. In general, these numbers are lower than the 43% illness rate reported in Scottish travelers,11 the 49% illness rate in Swedes12 or Americans.3 Although some of those studies were from the eighties and one could assume a possible change in risk-prone behaviors amongst young and elderly populations alike, similar results are reported in more recent series of American and Israeli travelers (64% and 70%, respectively).2,13 A possible explanation is the relatively short duration of travel in our study, since for all destinations the risk of illness has been correlated with travel duration regardless of age.2

Diarrhea was the most common complaint in both groups and was experienced significantly less often by the elderly travelers (10% vs 25%). This percentage of travelers with diarrhea is similar to that reported in other studies which ranged from 20% to over 50%.2,9,10,13,14 Diarrhea was also found to be the predominant complaint of younger travelers after returning home (3.44% vs 0.52% amongst the elderly and the younger travelers, respectively, p = 0.04). Aging reduces stomach acidity, an important protective factor against diarrhea-causing organisms. Acidity might also be reduced by diabetes and by certain medications such as histamine receptor blockers and proton pump inhibitors. Yet, elderly travelers had a lower incidence of diarrhea, possibly because they frequently go to better restaurants and are less adventurous eaters.

As in other studies,2,13 respiratory tract symptoms were the second most common reported illness. Most febrile episodes were associated with diarrhea and respiratory symptoms and consequently occurred significantly less often in elderly travelers.

The association between old age and decreasing health risks has been reported elsewhere.2,9 However, it has consistently been explained by a shorter duration of travel, a factor that was eliminated in our study. As presented here, the lower incidence of illness during and after travel in our patients was due to adherence to health-related recommendations and travel mode.

Other adverse health events occurred with less frequency, although some have important implications. Elderly travelers might be less physically fit than younger travelers and thus are more prone to injury. Two elderly travelers sustained traumatic falls, one of which necessitated orthopedic surgery after returning home. Significantly more elderly travelers reached heights above 1,500 m and used acetazoleamide for mountain sickness prophylaxis compared to the younger travelers (26% vs 12%, respectively). Even though high-altitude illness is much more likely to occur at altitudes higher than 2,500 m than at lower altitudes,15 it is being increasingly recognized at altitudes between 1,500 and 2,500 m.16,17 Since we wished to detect any minor symptom, a cut-off of 1,500 m was chosen for mountain sickness assessment. None of the travelers had symptoms suggesting mountain sickness. This is in agreement with the study of Cooper et al. which suggested that healthy elderly travelers can easily tolerate stays at moderate altitudes.18

Multivariate analysis demonstrated that only travel to East Asia (OR 4.66) and backpacking (OR 1.94) were associated with illness. The fact that backpacking mode of travel and not age or eating and drinking habits was associated with illness might suggest that the environmental health hazards, both those associated with the destination and those associated with personal exposure, affect the health of the traveler. The environmental factors are probably more complex, extending beyond food and drink hygiene. These might include variables such as efficient sewage systems in the boarding facility, crowding, personal hygiene, and parasite infestations.

Interestingly, illness in our study was associated with traveling to East Asia, while visiting India was not associated with an increased risk of illness. While 38% of the travelers visiting Thailand reported an illness, only 24% of those visiting India did so. This is in contrast to studies by Rack et al. and Greenwood et al. that found visiting India to be an increased risk.9,19 A possible explanation for our finding might be that Thailand has become an increasingly popular destination in recent years among Israeli travelers of all ages. Its perception as a developing country has been consistently eroded, a process that has been accompanied by an increasing disregard for the recommended dietary restrictions by Israeli tourists. India, on the other hand, is still perceived as carrying high health risks. Another possible explanation is that our cohort of short-term travelers differs substantially from the cohorts included in the GeoSentinel study. The majority of our cohort of travelers to India were adults who traveled in organized tours for less than a month, and not backpackers traveling for several months, who constitute many of the GeoSentinel study participants.

Elderly travelers were significantly more compliant with anti-malarial medications prescribed as chemoprophylaxis than younger travelers (61% vs 34%, respectively). This is in accordance with the rates reported in other surveys of European, North American, and Israeli travelers.2,9,13,20 Many travelers, especially younger ones, fear the potential side effects of anti-malarial drugs, particularly neuropsychiatric problems associated with mefloquine. This was stated as a reason for not taking these medications by 29% of the younger travelers compared to only 7% of elderly travelers who did not take chemoprophylaxis as recommended. Perhaps as a compensatory measure, significantly more of the younger travelers used mosquito repellants (60% vs 47%) for protection.

One possible limitation of our study was that the study participants were approached at a relatively later phase, eg, 4 to 10 months after their return. Some minor disorders might have been forgotten after such a delay. However, since the differences observed were substantial (eg, median duration of diarrhea of 5.1 days compared to 2.7 days in the older and younger travelers group, respectively) and since both groups were approached at the same time frame, we believe they are real and do not reflect a recall bias.

Elderly travel to the developing world is constantly increasing. Although elderly travelers present with more ongoing medical issues their risk for illness during travel is low. Travel conditions and visiting East Asia independently increase the risks of becoming ill, regardless of age. Thus, elderly travelers can be reassured that age per se does not necessarily pose excessive risks.

Declaration of Interests

The authors state they have no conflicts of interest to declare.

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