TABLE 2

Clinical characteristics of 76 participants with early Lyme disease grouped by clinical outcome

CharacteristicLyme disease patientsaP valueb
PTLDS (n = 11)Symptoms only (n = 29)Return to health (n = 36)Total (n = 76)P vs SP vs RS vs R
% participants with physician-documented:
    EM lesions100.00100.00100.00100.00NANANA
    Disseminated EM9.0934.4836.1131.580.230.140.89
Time from first symptom to initiation of antibiotic treatment (days)0.470.720.35
    Median6757
    IQRc3–105–103–144–11
    Range3–421–352–351–42
% participants seropositived45.4574.0772.2268.920.140.150.87
No. of self-reported symptomse
    Acute phase, pretreatment0.730.080.24
        Median121099
        IQR10–156–166–126–14
        Range4–190–221–170–22
    Posttreatment follow-up0.290.070.19
        Median17131011
        IQR8–218–188–128–17
        Range4–244–243–243–24
    1-mo follow-up0.050.020.79
        Median10344
        IQR2–141–70–61–8
        Range0–240–220–150–24
    3-mo follow-up0.070.0040.07
        Median7312
        IQR2–121–60–31–6
        Range1–220–210–150–22
    6-mo follow-up0.220.0020.002
        Median6423
        IQR3–93–70–31–6
        Range1–230–190–100–23
    1-yr follow-up0.002<0.001<0.001
        Median13413
        IQR8–193–100–30–8
        Range6–340–160–120–34
  • a Participants were grouped by clinical outcome using a previously published definition incorporating both persistent symptoms and functional impact (25).

  • b Significance was determined by the chi-square or Fisher's exact test for disseminated erythema migrans lesions and seropositivity and the Wilcoxon rank sum test for time from first symptom to antibiotic treatment and number of symptoms. P, participants with PTLDS; S, participants with symptoms only; R, participants who returned to health; NA, not applicable.

  • c IQR, interquartile range.

  • d Interpreted according to CDC guidelines for acute- and convalescent-phase two-tier ELISA and reflex Western blot (IgG/IgM) testing (24). Complete serologic data were missing for two symptoms-only group participants.

  • e Determined by use of an interviewer-administered checklist of 36 symptoms. Any new-onset symptoms since the time of diagnosis of early Lyme disease that were not explainable by other causes were considered present and included in the count. One participant from the symptoms-only group was missing complete symptom data at the posttreatment visit; three participants (one from the symptoms-only group, two from the return-to-health group) were missing complete symptom data at the 1-month follow-up visit, two participants from the return-to-health group were missing complete symptom data from the 3-month follow-up visit, and one participant from the PTLDS group was missing complete symptom data from the 1-year follow-up visit.