Predictors of Post-Infectious Chronic Fatigue Syndrome in Adolescents, 2014, Jason et al

[Dolphin]

Split from here.


Health Psychol Behav Med. 2014 Jan 1;2(1):41-51.
Predictors of Post-Infectious Chronic Fatigue Syndrome in Adolescents.
Jason LA1, Katz BZ2, Shiraishi Y3, Mears CJ4, Im Y5, Taylor R6.
Author information

Abstract
This study focused on identifying risk factors for adolescent post-infectious chronic fatigue syndrome (CFS), utilizing a prospective, nested case-control longitudinal design in which over 300 teenagers with Infectious Mononucleosis (IM) were identified through primary care sites and followed. Baseline variables that were gathered several months following IM, included autonomic symptoms, days in bed since IM, perceived stress, stressful life events, family stress, difficulty functioning and attending school, family stress and psychiatric disorders. A number of variables were predictors of post-infectious CFS at 6 months; however, when autonomic symptoms were used as a control variable, only days spent in bed since mono was a significant predictor. Step-wise logistic regression findings indicated that baseline autonomic symptoms as well as days spent in bed since mono, which reflect the severity of illness, were the only significant predictors of those who met CFS criteria at 6 months.

KEYWORDS:
autonomic symptoms; chronic fatigue syndrome; longitudinal; mononucleosis; risk factors

PMID:

24660116

PMCID:

PMC3956649

 

[Hutan]

This 2014 paper is open access and pretty interesting.

On rates of CFS following glandular fever - 3 studies quoted finding about 10% of people have CFS at 6 months after diagnosis of glandular fever

Several studies have attempted to better define the relationship between EBV and CFS. White et al. (1998) assessed patients 16–65 years of age with either glandular fever (the British term for IM) or an upper respiratory tract infection (URI) for the development of fatigue and/or CFS. Nine percent of subjects with glandular fever, whether due to EBV or a different etiologic agent, were fatigued and complained of excessive sleeping at six months, compared with none in the URI group; symptoms appeared to be worse in the EBV-associated glandular fever group. Similarly, Buchwald et al. (2000) and Katz et al. (2009) found that 12% of adults and adolescents, respectively, met criteria for CFS six months following IM. Finally, Hickie et al. (2006) in the Dubbo Infection Outcomes Study showed an 11% rate of CFS six months following glandular fever (as well as two other similar, systemic infections common in Australia, Q fever and Ross River virus). In summary, about 10% of individuals do not fully recover from IM and meet the criteria for CFS six months following IM (Buchwald et al., 2000; Hickie et al., 2006; Katz et al., 2009; White et al., 1998).

This study: 301 adolescents recruited in Chicago; a baseline home-visit on average 2 months after diagnosis:

In the next stage, an initial baseline home-visit occurred, which included a blood draw, psychiatric interview, and an interview about symptoms and psychosocial functioning shortly after the time of infection.

At six-months, a telephone screening to check for CFS. Complete medical and psychiatric workup from adolescents with self-reported CFS and screened-negative controls. 39 cases and 50 controls.

Next, a follow-up telephone screening interview occurred six months post-infection to assess for self-reported symptoms of CFS. A complete medical and psychiatric work-up occurred for participants from the IM group that screened positive for self-reported CFS symptoms based on the six-month telephone interview and for screened-negative controls with efforts to match to subjects diagnosed with CFS by age, gender, and socioeconomic status. A larger number of controls than index cases were recruited. An independent team of physicians blind to condition reviewed each chart and reached diagnostic consensus regarding the presence or absence of CFS. The Jason et al. (2006) revision of the Fukuda (1994) criteria was used to diagnose CFS. When a well-recognized underlying condition, such as primary depression, could explain the subject's symptoms, s/he was classified as having “CFS-explained”.

 

[Hutan]

Of the 39 adolescents with CFS, 90% were female. The Jason et al revision of Fukuda was used to diagnose CFS - I don't know if that includes PEM or not.

Finding: (ASC = Autonomic Symptoms Checklist)

the only significant predictors were ASC and how many days were spent in bed since IM, indicating the importance of baseline severity variables. The variable “Any family stress around or prior to IM onset” was not found to be significant.

This suggests that indices of illness severity are the best predictors for adolescents destined to develop CFS following IM. It is reasonable to conclude from our study that during the first few months following IM, young people who have more limitations and are more impaired, are subsequently more likely to develop CFS. Our findings are thus comparable to those of Hickie et al. (2006), who followed patients with mononucleosis (glandular fever), Q fever, and Ross River virus who later met criteria for CFS. Development of CFS in their cohort was predicted largely by the severity of the acute illness rather than by demographic, psychological, or microbiological factors.

The lack of association between psychological factors and illness onset accords with my experience and that of my children. However, there do some to be some items quantified in this study associated with stress of various kinds that had some association with CFS onset. (See Table 2). The Perceived Stress Scale measures stress over the last month and could easily have been affected by being sick and so unable to meet obligations and enjoy life as normal. But the Life Events score also seemed to have a good P value, and that measures events over the preceding 12 months. The authors seemed to wave this away a bit, noting that the timing of the baseline survey meant that it probably included about 3 months of the 12 month period assessed for stressful events.

I guess what they tried to do was say, if we explain the likelihood of CFS onset as much as possible by this measure of illness severity (the Autonomic Symptoms Checklist), what other factors strengthen the predictive power of an equation? And they report that the only other predictive factor was days in bed. But there is mention of a checklist of of infectious symptoms that sounds like it might have been a better, more direct measure of the severity of IM symptoms:

The checklist of infectious symptoms is a self-report measure that has been used in a large-scale adult study of CFS following IM (Buchwald et al., 2000). It is a self-report measure of the presence and severity of IM symptoms. Questions regarding functioning included “Since mono, how many days have you spent in bed?”

Why, I wonder was a quantification of this checklist not used, rather than just the number of days spent in bed? I don't get a clear idea about the number of possible measures that could have been used to find associations.

I'm left wondering, what if someone said, 'I think the stressful events before and just after infection are the most important factor and ANS symptoms and number of days in bed are a result of that stress'? If the stepwise regression was done with the Life Events score first, what would happen?

I'm also not sure about the Jason et al version of Fukuda - does it include PEM?

I'm left feeling rather uncertain about whether this study proves the authors' hypothesis that severity of the IM illness is the primary predictor of CFS. I look forward to others' comments.