Effects of Comorbid Anxiety on Methylphenidate Treatment in the ADHD Child:
Medication with stimulants such as methylphenidate has consistently proven to be a popular and relatively effective mode of treatment for the ADHD child. However, questions arise regarding its side effects. In particular, the effectiveness of methylphenidate (Ritalin, Concerta, Daytrana, Metadate) can be jeopardized if the child with ADHD also has some type of comorbid disorder (such as depression, obsessive compulsive behaviors, Tourette's and a host of other common associate disorders) which may be negatively impacted by the ADHD treatment. Anxiety-related disorders are seen in up to 35% of ADHD individuals, according to some studies.
Typically, treatment is met with some type of adjunctive medication to treat the comorbid disorder (which can be quite tricky, as it introduces the problem of potential drug-drug interactions, as well as a possible impairment in the effectiveness of the ADHD treatment medication), a non-stimulant method of treatment such as Strattera (atomoxetine), or non-drug alternatives (behavior therapy, EEG, nutrition and dietary strategies, etc.). While isolated behavioral therapy has limitations for treating ADHD (especially in cases of "refractory" ADHD), it has proven to be a beneficial mode of treatment for childhood anxiety disorders.
In the case of anxiety disorders alongside ADHD, treatment with stimulant medications such as methylphenidate can also be tricky. However, recent findings seem to indicate that methylphenidate is a safe mode of treatment for ADHD with comorbid anxiety. However, a new publication notes that there may be a significant distinction between the effects of anxiety on methylphenidate's effectiveness from a behavioral standpoint vs. a cognitive standpoint. Let me explain further.
When attempting to determine whether a child should be diagnosed and treated as having ADHD, the supervising physician often gives out rating forms to both parents and teachers of the child in question. Numerical rating scales with regards to classic ADHD symptoms (i.e. impulsivity, hyperactivity, inattentiveness, etc.) comprise the majority of the rating forms, and these results are tabulated and typically used in the diagnostic process. Additionally, these rating forms are often administered after a specific period of time following treatment (with medication, nutritional therapies, counseling or ADHD coaching programs, etc.) to assess the effectiveness of these treatments.
While the level of agreement between parent and teacher rating forms is generally high, significant differences may often be seen. In other words, how a child's perceived behavior in the home may be notably different than his or her behavior in the classroom. While there are an array of possible factors and explanations for this, the presence of comorbid anxiety may be an important but often overlooked reason for this discrepancy.
In the study titled: Predicting Response of ADHD Symptoms to Methylphenidate Treatment Based on Comorbid Anxiety, the researchers found that the behavioral improvements in children with ADHD were similar regardless of whether the child also had an accompanying anxiety disorder. In other words, a notable decrease in symptoms of hyperactivity, impulsiveness and behavioral annoyances was frequently seen. Since these symptoms are often more of the obvious tell-tale signs of the disorder, it would be easy to conclude (especially from a parent's standpoint) that all is well again.
However, on the opposite side of the coin, the side dealing with the cognitive deficits of ADHD (which, not surprisingly have immense academic implications), may tell a different story. The study found that for the ADHD children without an accompanying anxiety disorder, methylphenidate treatment often contributed to vast improvements in their cognitive function (and subsequent academic achievement potential). However, if the ADHD child didhave an accompanying anxiety disorder, the methylphenidate treatment was significantly less effective (and possibly even counter-effective). This may serve as a possible explanation for at least some of the variability between parent and teacher evaluations of the same ADHD child.
This leads to the question: does comorbid anxiety affect the cognitive ability-enhancing effects in all academic areas or just in some of the sub-fields of academic-related cognitive functioning?
The study investigated this by administering a Weschler Intelligence Test ( WISC III ) to the children and examined the effects of comorbid anxiety and methylphenidate medication on three subcomponents of the test: Coding, Arithmetic and Symbol Search. An explanation of the results in these three subcategories with regards to what they measure, possible implications of these subcategories, and the effects of anxiety and methylphenidate treatment are summarized below:
Of the 3 subtests, methylphenidate treatment helped the most in the coding section, had minimal effects in the symbol search section and little (for the non-anxiety group) to no or negative (for the anxiety group) effects for the arithmetic section.
Other studies have also investigated the effects of comorbid anxiety on cognitive task performance in ADHD children. By and large, it appears that memory-based tasks are the hardest hit by an accompanying anxiety disorder when methylphenidate is administered as an ADHD treatment. Other studies have confirmed this finding on anxiety disorders impeding memory enhancement via methylphenidate treatment. This seems to agree with the data on the coding section, which involves a type of working memory for the symbol deciphering process.
Based on what we have covered here, it would be reasonable to scrutinize significant differences between parent and teacher ratings and behavioral and attentive improvements for the possibility of an accompanying anxiety disorder to go along with an ADHD diagnosis in a child. While anti-anxiety medications can be useful, and co-administered with ADHD stimulant drugs under the watchful eye of a carefully trained physician, there is also evidence that
These findings suggest that comorbid anxiety can be a serious handicap to achieving cognitive and academic-related improvements in response to stimulants such as methylphenidate. However, please note that, based on the main study of our discussion onADHD, anxiety and methylphenidate, notable behavioral improvements were seen from methylphenidate treatment in both the ADHD + anxiety and the ADHD minus anxiety groups.
The implications of this discrepancy can be noteworthy. To the parent who is only marginally involved with their child's academic progress, and is simply concerned with getting more manageable behavior out of their ADHD child, the sharp reduction of negative behavioral symptoms may lull the parent into a false sense of security that all is well on the home front. This stratified response to the methylphenidate medication may be lost to the unassuming parent.
However, it may be possible that an accompanying anxiety disorder (and maybe even an auditory processing disorder) may be lying there dormant to the oblivious parent. For the teacher, however, an improvement in classroom behavior due to medication, but a lack of improvement in academic work (especially in memory-related tasks) may be a tip-off that an undiagnosed accompanying anxiety disorder may be in place in this ADHD child. Thus this discrepancy in medication-derived improvements may actually serve as a potentially powerful diagnostic tool for detecting an accompanying anxiety disorder in a child being treated for ADHD.