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             DISTRICT OF COLUMBIA COURT OF APPEALS

                                  No. 19-AA-335

                           MARIA RAMOS, PETITIONER,

                                         V.

                          DISTRICT OF COLUMBIA
             DEPARTMENT OF EMPLOYMENT SERVICES, RESPONDENT,

                                        and

                         P&R ENTERPRISES, INC. and
                 TRAVELERS INSURANCE COMPANY, INTERVENORS.

                     On Petition for Review of an Order of the
            District of Columbia Department of Employment Services
                           Compensation Review Board
                                    (CRB-4-19)

(Argued March 13, 2020                                     Decided May 28, 2020)

       Carlos A. Espinosa, with whom Ivan M. Waldman, was on brief, for
petitioner.

       Caroline S. Van Zile, Deputy Solicitor General, with whom Karl A. Racine,
Attorney General, and Loren L. Alikhan, Solicitor General, filed a statement in lieu
of a brief, for respondent.

      Amy L. Epstein for intervenors.

      Before GLICKMAN, EASTERLY, and DEAHL, Associate Judges.
                                         2

      DEAHL, Associate Judge: Maria Ramos suffered a stroke in the course of her

custodial work. She brought a claim for workers’ compensation benefits under the

District of Columbia Workers’ Compensation Act. See D.C. Code §§ 32-1501, et

seq. (2019 Repl.). The Administrative Law Judge (ALJ) denied her claim, and the

Compensation Review Board (CRB) affirmed that denial, each concluding that her

stroke was not causally related to her work. Ms. Ramos now appeals the CRB’s

judgment.



      The Workers’ Compensation Act affords claimants a presumption that an

injury is causally connected to their work, and therefore compensable, whenever

they present “some evidence” of “a work-related event, activity, or requirement

which has the potential of resulting in or contributing to the death or disability.”

Ferreira v. District of Columbia. Dep’t of Emp’t Servs., 531 A.2d 651, 655 (D.C.

1987); D.C. Code § 32-1521(1). Once triggered, the employer may sever this

presumed causal connection only by presenting “substantial evidence” “specific and

comprehensive enough to sever the potential connection between a particular injury

and a job-related event.” Ferreira, 531 A.2d at 655 (quoting Swinton v. J. Frank

Kelly, Inc., 554 F.2d 1075, 1083 (D.C. Cir. 1976)). The CRB reasoned that while

Ms. Ramos had triggered the presumption of causality—a finding that is not
                                          3

challenged here—her employer presented substantial evidence sufficient to rebut

that presumption. We disagree. We reverse and remand for further proceedings.



                                          I.



      Ms. Ramos worked as a janitor for P&R Enterprises, Inc. Her job involved

emptying trash cans and cleaning offices on two floors of a large office building that

spanned a city block. According to her credited testimony, the trash cans were often

filled with books and paper so that they could be “very heavy,” 1 and she had to move

quickly in order to complete her work within her five-hour shift. On April 19, 2016,

Ms. Ramos was working hurriedly when, about halfway through her five-hour shift,

a “heat wave” came over her, her extremities went numb, and she collapsed. She

got up only to collapse again. Ms. Ramos’s supervisor called for an ambulance

which transported her to the hospital where she was diagnosed as having suffered

from a hemorrhagic stroke.




      1
         Ms. Ramos’s supervisor estimated that even when filled to the brim with
paper or books, each trash can Ms. Ramos had to lift would weigh only “10 pounds
approximately.” The larger receptacle that she emptied the smaller cans into was on
wheels so that she would only have to push rather than lift it.
                                          4

      Ms. Ramos’s stroke did not come without warning. She was diabetic and had

a history of hypertension, as well as a pattern of skipping the medications prescribed

to control her high blood pressure. Eight months before her stroke, she was admitted

to the hospital following an automobile accident and her blood pressure was

measured at an alarming 242 (systolic) / 152 (diastolic).2 In the months following

her stroke, Ms. Ramos’s treating physician, Dr. Claudia Husni, opined that her stroke

was “a consequence of” her hypertension, further noting that the stroke had left her

permanently unable to use her left hand and arm.



      Ms. Ramos filed a claim for workers’ compensation benefits and ultimately

requested a formal hearing before an ALJ. Ahead of the hearing, the parties

indicated that the only contested issue between them was whether Ms. Ramos’s

stroke was causally related to her employment. The medical evidence as to that

question came primarily from Dr. Allen A. Nimetz, who at the request of the

employer, performed an independent medical evaluation of Ms. Ramos and


      2
         As a reference point, Dr. Nimetz testified that high blood pressure was once
defined as anything above 140 systolic and 90 diastolic, and that those numbers had
dropped even lower in the year prior to his testimony. Ms. Ramos’s 242 / 152
reading was well past the point that qualifies a person as being in the midst of a
hypertensive crisis.       See High Blood Pressure, AM. HEART ASS’N,
https://www.heart.org/en/health-topics/high-blood-pressure (categorizing a person
with blood pressure higher than 180 (systolic), or higher than 120 (diastolic), as
experiencing a hypertensive crisis).
                                          5

examined her medical records. Dr. Nimetz testified and authored a report that was

admitted into the record. In his report, he opined that “[t]he major contributory

factors [of Ms. Ramos’s stroke] were uncontrolled hypertension and poorly

controlled diabetes mellitus,” and he concluded, “I would not attribute the

cerebrovascular event [to] her employment.” He repeated that conclusion in his

testimony, noting that Ms. Ramos’s diabetes and high blood pressure were

conditions that “she brought into work when she started,” leading him to conclude

that she did not suffer “a work related injury or work related disease.”



      On cross-examination, Dr. Nimetz agreed that physical exertion will increase

a person’s blood pressure, including a person who already has high blood pressure,

and agreed that strokes could result from high blood pressure. The ALJ then

intervened and asked Dr. Nimetz, who had heard Ms. Ramos’s testimony, whether

he had “an opinion as to whether or not [Ms. Ramos’s] job responsibilities would in

any way cause her to have the stroke.” He replied, “No. I have not witnessed what

the responsibilities involve, and not looking at how much heavy duty it is, what the

environment is. So I really can’t make a[n] opinion on that.”



      In her closing arguments before the ALJ, Ms. Ramos maintained that her

stroke was brought on by aggravation of her hypertension. She argued that injuries
                                         6

are compensable even when the work merely contributes to the injury by aggravating

a pre-existing condition, and that the evidence—including Dr. Nimetz’s own

testimony—was sufficient to trigger the presumption of compensability.          In

response, the employer pointed out that neither Dr. Nimetz nor Ms. Ramos’s treating

physicians ever stated that Ms. Ramos’s employment responsibilities caused her

stroke. The employer argued that Ms. Ramos was not even entitled to a presumption

of causation because there was no medical evidence showing a causal relationship

between her work responsibilities and her stroke.



      The ALJ found that Ms. Ramos had produced enough evidence to trigger the

statutory presumption of compensability but that Dr. Nimetz’s report and testimony

constituted “substantial evidence” rebutting the presumption. Having disposed of

the presumption, the ALJ concluded that Ms. Ramos had not proven causation by a

preponderance of the evidence. The compensation order dismissed Ms. Ramos’s

claim without mentioning her aggravation theory specifically, although it did note

Dr. Nimetz’s opinion that hypertension and diabetes were the “major contributory

factors” of the stroke.



      Ms. Ramos sought review by the CRB, contending that the ALJ had

improperly found that the presumption had been rebutted. She reiterated her
                                           7

argument that Dr. Nimetz’s testimony about elevated blood pressure supported her

theory of causation. In its response, the employer abandoned its argument that Ms.

Ramos did not present sufficient evidence to trigger the presumption that her stroke

was causally related to her employment. It instead relied upon its argument that it

had adequately rebutted that presumption with “substantial evidence,” as the ALJ

had found.    The CRB agreed, concluding that “Dr. Nimetz . . . rendered an

unambiguous opinion that Claimant’s stroke was not causally related to her

employment.”3 The CRB discounted Dr. Nimetz’s cross-examination testimony that

he had no opinion as to whether Ms. Ramos’s “job responsibilities would in any way

cause her to have the stroke” as mere “answers to [] hypothetic questions, which we

do not equate to be substantial evidence.” The CRB affirmed the ALJ’s conclusion

that the presumed causal connection between Ms. Ramos’s work and her stroke had

been rebutted by “substantial evidence.”




      3
        The CRB described this as an “undisputed” point, a misplaced descriptor as
this was the central point of the dispute before it. See Ms. Ramos’s Mem. in Supp.
of Appl. for Review at 10 (Feb. 13, 2019) (“Dr. Nimetz’s testimony . . . provided a
clear causal connection between Ms. Ramos’s work related injury and her
employment.”).
                                           8

                                          II.



      The only issue presented on appeal is whether the employer, P&R Enterprises,

presented substantial evidence sufficient to rebut the presumption that Ms. Ramos’s

stroke was causally related to her work. 4 While we defer to the factual findings

below, what constitutes substantial evidence sufficient to rebut the presumption that

one’s work is causally related to their injury is a legal question that we review de

novo. See Washington Post v. District of Columbia Dep’t of Emp’t Servs., 852 A.2d

909, 914 (D.C. 2004) (quoting Safeway Stores, Inc. v. District of Columbia Dep’t of

Emp’t Servs., 806 A.2d 1214, 1219 (D.C. 2002)). We review the CRB’s final order,

mindful that “we cannot ignore the compensation order which is the subject of the

Board’s review.” Georgetown Univ. Hosp. v. District of Columbia Dep’t of Emp’t

Servs., 916 A.2d 149, 151 (D.C. 2007).




      4
           The employer does not dispute that Ms. Ramos presented evidence
sufficient to trigger the legal presumption of causation. For her part, Ms. Ramos
does not dispute that she cannot prevail if that legal presumption was in fact rebutted,
as that would have left her with the burden of proving causation by a preponderance
of the evidence, see McCamey v. District of Columbia Dep’t of Emp’t Servs., 947
A.2d 1191, 1214 (D.C. 2008) (en banc), and she does not purport to have carried
that burden. Ms. Ramos’s sole point of contention is that the employer’s evidence
“does not raise [sic] to the level of substantial evidence required under the Act.”
                                            9

      In analyzing the issue presented, it helps to first identify the precise target that

substantial evidence was needed to rebut. The only theory of causation offered by

Ms. Ramos, and the only one supported by some evidence, was that her work as a

custodian involved physical exertion, which in turn may have raised her already high

blood pressure, which in turn had the potential to trigger her stroke. As her counsel

argued in closing, the evidence supported the possibility (at least enough to trigger

the presumption of causality) that her high blood pressure “coupled with her

activities at work” caused her stroke. Ms. Ramos reiterates on appeal that it was this

theory that triggered the presumption in her favor—that her “stroke was caused as a

result if [sic] her hypertension coupled with the normal blood pressure increase due

to her physical exertion while doing her job”—and the employer does not contest

that understanding or offer any alternative to it. 5



      Put another way, Ms. Ramos’s theory was that her work aggravated her pre-

existing hypertension. It is undisputed and well-established that this is a valid theory



      5
         The ALJ found that Ms. Ramos triggered the presumption of causality
because she “was emptying the trash at the time she fell and as a result was diagnosed
with a hemorrhagic stroke,” and the CRB did not revisit the question because it was
uncontested before it. The ALJ’s finding, while somewhat opaque, is best
understood as a nod to Ms. Ramos’s causal theory that the strain of her work
exacerbated her high blood pressure thereby triggering a stroke and, in any event,
that understanding is undisputed here.
                                         10

of compensability under the Workers’ Compensation Act. See King v. District of

Columbia Dep’t of Emp’t Servs., 742 A.2d 460, 468 (D.C. 1999) (citing Ferreira,

531 A.2d at 660). Under our “aggravation rule,” it does not matter that work-related

activities may have contributed to the injury only in part, that the injury would not

have happened but for a pre-existing condition, or that the injury “might just as well

have been caused by a similar strain at home or at recreation.” Id. (quoting Wheatley

v. Adler, 407 F.2d 307, 312 (D.C. Cir. 1968) (en banc)). Whether Ms. Ramos was

teetering on the edge of a stroke independent of her work is thus beside the point; if

her work inched her over that edge, however slightly, her injury is compensable.



      Having nailed down the theory to be rebutted, we turn to whether the employer

presented substantial evidence to accomplish that feat. We as a court have not

endeavored to pinpoint a “precise quantum of proof needed to meet the substantial

evidence threshold.” Washington Hosp. Ctr. v. District of Columbia Dep’t of Emp’t

Servs., 744 A.2d 992, 1000 (D.C. 2000). Instead we have said that “substantial

evidence” means evidence that is “specific and comprehensive enough to sever the

potential connection between a particular injury and a job-related event.” Ferreira,

531 A.2d at 655 (quoting Swinton, 554 F.2d at 1083).
                                          11

      Critical to this case is that an employer’s substantial evidence must address

the employee’s specific theory of causation. Our recent opinion in Battle illustrates

the point. Battle v. District of Columbia Dep’t of Emp’t Servs., 176 A.3d 129 (D.C.

2018). In Battle, the employee triggered the presumption of causality by presenting

some evidence that the cumulative impact of driving a bus for many years had caused

or aggravated his back condition. Id. at 131–32. The employer’s expert opined that

the back condition was not job-related because it was not caused by any single

incident. Id. at 135. But, we explained, “this was not the theory of causation that

[the employee] advanced.” Id. The employer had failed to address the employee’s

“cumulative impact” theory altogether. Id. “If the employer fails to address and

rebut [the employee’s] theory with substantial evidence, the presumption of

compensability stands.” Id. at 136. The employer in Battle had failed to rebut the

presumption with evidence that was “specific and comprehensive enough” to sever

the potential connection. Id. at 135.



      So too here.     Dr. Nimetz’s report and testimony were generally non-

responsive to Ms. Ramos’s aggravation theory, and when he was ultimately pressed

on it, he was agnostic. In his report, Dr. Nimetz opined that “[t]he major contributory

factors” to Ms. Ramos’s stroke “were uncontrolled hypertension and poorly

controlled diabetes,” and that he “would not attribute” Ms. Ramos’s stroke to “her
                                          12

employment.” Those opinions do not address much less undermine Ms. Ramos’s

aggravation theory. The relevant question is not whether her work was the most

dominant or even a major contributory factor to her stroke; it is whether it was a

contributing factor, a question Dr. Nimetz’s report does not opine on. 6 While Dr.

Nimetz opined that he would not attribute the stroke to her work, that statement in

context suggests that he would attribute Ms. Ramos’s stroke only to the major

contributing factors, to wit, the two major contributory factors he had just identified

(diabetes and high blood pressure). That is in fact the only plausible explanation

given that Dr. Nimetz admitted in his testimony that he did not know anything about

Ms. Ramos’s work activities when authoring his report. 7 His opinion was based


      6
        For the same reason, the underlying medical records and statements by other
doctors do not constitute substantial evidence either. For example, Dr. Husni’s
statement that the stroke was “a consequence of” Ms. Ramos’s hypertension is
undoubtedly true, but consistent with aggravation, as explained above.
      7
         During his testimony Dr. Nimetz indicated that Ms. Ramos’s work “never
came up when [he] saw her,” and as to the strain of her work, he could “only judge
from what she said today.” As discussed further below, once he learned of Ms.
Ramos’s work responsibilities Dr. Nimetz became agnostic in his testimony about
whether they contributed to her stroke. As discussed supra note 1, there was at least
some tension between Ms. Ramos’s description of her lifting “very heavy” waste
bins and her supervisor’s testimony that the bins would weigh about ten pounds
when full, but neither Dr. Nimetz nor any other evidence suggested that discrepancy
was of any import. In finding the presumption of causation rebutted the ALJ and
CRB referred to Dr. Nimetz’s report, his testimony, and Ms. Ramos’s medical
records—none of which addressed whether the job’s manual labor was insufficiently
strenuous to contribute to her stroke. There is nothing in the supervisor’s opinion
about the weight of the trash cans that, even if credited over Ms. Ramos’s testimony,
                                          13

largely on her medical records’ failure to attribute the stroke to her work

responsibilities, and we do not think those records’ silence on the point can constitute

substantial evidence any more than Dr. Nimetz’s agnosticism could. 8



      Dr. Nimetz’s testimony drives home the point that the opinions in his report

were non-responsive to Ms. Ramos’s aggravation theory. The one time he was asked

to home in on the aggravation theory and express an opinion about how likely it was

that Ms. Ramos’s work triggered her stroke, Dr. Nimetz was utterly agnostic. When

the ALJ asked Dr. Nimetz whether he had any opinion “as to whether or not [Ms.

Ramos’s] job responsibilities would in any way cause her to have the stroke,” he

responded with a resounding “No,” that he had formed no “opinion on that.” Read

in light of that important concession, Dr. Nimetz’s other statements attributing Ms.



could meaningfully contribute to a finding of substantial evidence rebutting Ms.
Ramos’s theory. It is undisputed that Ms. Ramos’s work consisted of some manual
labor, and the potential that it contributed to her stroke was not rebutted, regardless
of the precise strain her work involved.
      8
          Treating physicians may quite reasonably identify the predominant causes
for medical events without surveying the universe of more minor contributing
causes, or opine about physiological causes for injuries without cataloging broader
environmental causes. Without some evidence that Ms. Ramos’s treating physicians
considered whether the nature of her work was a potential cause of her stroke, we
do not construe their silence on that question as answering it in the negative. Just as
Dr. Nimetz lacked (and expressly disavowed) any relevant knowledge about whether
Ms. Ramos’s work involved the sort of activity that would contribute to a stroke,
there is every reason on this record to think her treating physicians did likewise.
                                          14

Ramos’s stroke to her pre-existing conditions are unilluminating and beside the

point. The CRB was thus wrong to conclude “that Dr. Nimetz . . . rendered an

unambiguous opinion that Claimant’s stroke was not causally related to her

employment.” He rendered no opinion at all about that. He offered only non-

sequiturs and, once focused on this critical question, agnosticism.



      Wheatley v. Adler, 407 F.2d 307 (D.C. Cir. 1968) (en banc), is instructive.

There, Mr. Wheatley had a pre-existing condition—“arteriosclerotic heart

disease”—and suffered a fatal heart attack on the job. Id. at 309. Just before his

heart attack, Mr. Wheatley had urinated outside in the cold, and his widow presented

evidence that “the strain of urinating on a cold day could have” triggered his heart

attack. Id. at 310. The employer’s medical expert testified and, “assuming in

hypothetical form [Mr. Wheatley’s account of his day] (including the urinating in

the cold),” opined that his death “was not the result of any activity involved” in Mr.

Wheatley’s employment. Id. The expert reiterated the conclusion, “that the attack

was in no way related to his employment.”           Id.   But when asked on cross-

examination to focus on the particular aggravation theory presented by Mr.

Wheatley, like here, the expert offered no opinion at all: “Asked whether [urinating

in the cold] was more likely than not the cause, he said he could not really give a yes
                                         15

or no answer.” Id. at 311. 9 That record, the court concluded, did not “contain

substantial evidence to dispel the statutory presumption” of causation and the court

reversed the finding that Mr. Wheatley’s heart attack “did not arise out of and in the

course of his employment” Id. at 309, 314. Wheatley compels the same result here.



      It bears stressing that substantial evidence need not be conclusive or even

particularly compelling; but it does need to be targeted. An employer need not show,

in order to rebut the presumption of causation, that causation was “impossible.”

Safeway Stores, 806 A.2d at 1220 (quoting Washington Hosp. Ctr., 744 A.2d at

1000). It need only present evidence that “a reasonable mind might accept as

adequate to support” the conclusion that there was no causal link between the

employment and the injury. Washington Post, 852 A.2d at 914. For example, if Dr.

Nimetz had opined that Ms. Ramos’s exertion at work was unlikely to have triggered

her stroke, that bare expression of unlikelihood might have cleared the substantial

evidence bar. See, e.g., Wheatley, 407 F.2d at 313 (to rebut the presumption of

causation on an aggravation theory, one “at least” would have “to articulate that this



      9
          The court in Wheatley acknowledged that “[c]omplaints have been voiced
against the aggravation rule as applied to cardiac cases” but noted that precedent
nonetheless dictated its application and that any desired change in the rule would be
“appropriately addressed to Congress.” 407 F.2d at 312. There is no dispute here
that the aggravation theory presented by Ms. Ramos was a valid one.
                                        16

possibility was improbable”). Yet Dr. Nimetz disavowed any such opinion and no

other evidence directly addressed the aggravation theory. The presumption was

therefore unrebutted and Ms. Ramos’s claims are compensable.



                                        III.



      We reverse the decision of the CRB and remand for further proceedings

consistent with this opinion. Given our conclusion that there was insufficient

evidence to rebut the presumption of compensability, the issue is not subject to

reconsideration on remand. See Battle, 176 A.3d at 136 (citing Parodi v. District of

Columbia Dep’t of Emp’t Servs., 560 A.2d 524, 526 & n.5 (D.C. 1989)).



                                                          So ordered.
